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TENTH EDITION 

MANUAL A 

OF 

Modern Surveyin 
Instruments 

AND THEIR USES 

TOGETHER WITH A 

CATALOGUE & PRICE LIST 

OF 

SCIENTIFIC INSTRUMENTS 

MADE BY 

1 he A. Lietz Lompan 

Established 1882 

632-634 Commercial Street 

SAM fpam-t SCO| CALIFORNIA 
LIBRARY OF CONGRESS 

908 




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CENTS 



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A Manual 
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Surve 
ing and Mir 




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Copyright}! 



COPYRIGHT DEPOSIT: 



IONS: 



heir uses — 
tgineer and 
, Engineer- 



Price List of Surveying, Engineering and Mining Instru- 
ments and Engineers' Field Supplies. Free. 



B 



Price List of Nautical Instruments (for Navigators only.) 
Free. 



Price List of Office Supplies for Engineers, Architects and 
Draughtsmen. Free. 



'HIS MANUAL was written expressly for this Company, and the matter 
therein contained is protected by a copyright. Parties infringing will be 
prosecuted. 



TELEGRAPHIC CODE 

To Accompany the Tenth Edition of the Manual of Modern Survey- 
ing Instruments and Their Uses, Together with 
Catalogue and Price List. 



A. LIETZ CO. 

San Francisco, Cal. 



cable address : CYCLOTOMIC, San Francisco 
We have A. B. C, Fourth Edition, and the Following Code. 



Transits and transit theodolites, except No. 22, are supplied with 
solid silver graduations (unless ordered to the contrary), and all complete 
transits and transit-theodolites are furnished with stadia lines, fixed 1 : 100 (unless 
ordered to the contrary). 

Catalogue No. TRANSITS. Code Word. 

No. 1 Bugbear 

2 Buggy 

3 Buglehorn 

4 Bugler 

6 Building 

7 Bulbous 

8 Bulged 

9 Bulimy 

10 Bulkiness 

" 11 Bullace 

- 12 Bullcalf 

" 16 ' Bulldog 

" 17 Bulletin 

PRELIMINARY TRANSITS. 
No. 22 Bullock 

TRANSIT THEODOLITES. 

No. 5 Bulltrout 

13 Bulrush 

Y LEVELS. 
No. 19 Bumboat 

DUMPY LEVELS. 

No. 20 Bumper 

;; 20A Bumkin 

21 Bumptious 



EXTRAS FOR TRANSITS AND LEVELS. 

Made of Hard Aluminum Alloy Culotte 

Verniers Reading to 30 sec. on Horizontal Circle Cullyism 

20 sec. " " Culminate 

Gradienter Attachment Culpable 

Variation Plate Culprit 

Arrangements for Offsetting Right Angles Cultivate 

Striding Level to Axis of Telescope Cultrated 

Reversion Level to Telescope Culture 

Constructed with 3 Leveling Screws instead of 4 Culverin 

3 Leveling Screw Shifting Center Cumber 

Prism to Eye-piece Cumbersome 

Extension Tripod in Lieu of Ordinary Cumbrance 

Saegmiiller Solar Attachment Cumbrous 

Guard for Vertical Circle Cumshaw 

Half Length Tripod Cumulus 

Detachable Side Telescope Cuneated 

Reflector for Illuminating Cross-Hairs Cuneiform 

Quick Leveling Tripod Attachment Cunning 

Vertical Circle Graduated on the Periphery Cupbearer 

Telescope Inverted Cupboard 

Mirror to Control Bubble at Eye End Cupid 

Agate Fitted Y's Cupidity 

Stadia Hairs Fixed Cupola 

Adjustable Cupping 

Split Tripod Legs in Lieu of Ordinary Curdiness 

EXTRAS FOR TRANSIT THEODOLITES. 

Verniers Reading to 20 sec. on a 6 I /i in. Horizontal Circle Cupreous 

Verniers Reading to 10 sec. on a 7 in. Horizontal Circle Curable 

A 5 in. Vertical Arc Reading to Minutes Curacy 

A 5 in. Full Vertical Circle Reading to Minutes Curateship 

A 5 in. Full Vertical Circle with Opposite Double Verniers Reading 

to Minutes Curative 

Two Vernier Microscopes Curbing 

Long Ground Level to Telescope with Compound Clamp and Tangent 

Screw Telescope Reversible, Supplied with Gradienter Curbstone 

Box Needle on Plate Curbles 



TENTH EDITION 



MANUAL A 



OF 



Modern Surveying 
Instruments 

AND THEIR USES 

TOGETHER WITH A 

CATALOGUE & PRICE LIST 

OF 

SCIENTIFIC INSTRUMENTS 

MADE BY 

1 he A. Lietz Lompany 

Established 1882 

632-634 Commercial Street 

SAN FRANCISCO, CALIFORNIA 
1908 



PRICE, 50 CENTS 



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? ^9 



V 



|LIBRARYo(OONSRE$S. 

TwtoMn tuetnM 

JAN 10 1908 

wowm*<« &Ntry 
p^ c\ L40J 

w a. 



COPYRIGHTED, 1907 
THE A. LIETZ CO. 



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NOTICE 



y I V HIS Manual supersedes the former edition of our catalogue, 
and is carefully revised and corrected to date. 

The articles manufactured by this Company are quoted at 
prices consistent with the quality of workmanship and material. 
We endeavor to place before -.the-.piivbiic an equivalent of the very 
best that can be obtained, without imitating in shape or design 
any make whatever. All our articles are of the most recent 
standard, with every known improvement. 

The Lietz Instruments are well known to the profession, hav- 
ing been made under the personal supervision of our Mr. Lietz 
since 1882 ; and with our new building and the latest improved 
machinery, designed to meet our peculiar methods of obtaining 
the highest results, we are producing the nearest to perfection at 
moderate prices. 

Distant purchasers will please remit by check, money order, 
or registered letter, or order C. O. D. 

According to the rules of Wells, Fargo's Express Company, 
a surveying instrument, carefully placed in its case and in a pack- 
ing box, is shipped as merchandise and charged at "single rate." 
"Three rates" will be charged if this precaution be not taken. The 
customer should not omit, therefore, to pay strict attention to this 
rule of the express company and avoid unnecessary overcharges. 

Packing boxes are furnished by us at a nominal rate. 




THE A. LIETZ CO. BUILDING 

Before the San Francisco Catastrophe of April 18, 1906. 




THE A. LIETZ CO. BUILDING 



After the San Francisco Catastrophe of April 18, 1906. 




THE NEW A. LIETZ CO. BUILDING 

Fifteen months after the San Francisco Catastrophe of April 18, 1906. Entirely reinforced 

concrete, wired-glass windows, metal window frames, self-closing. Secures 

greatest stability for precision work. 




GENERAL OFFICE. 



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EAST SIDE OF SALES DEPARTMENT. 




MACHINE AND TOOL MAKING. 



Second Floor. 




STORE-ROOM. 




ASSEMBLING AND ADJUSTING DEPARTMENTS, 



Third Floor. 




MANUFACTURING DEPARTMENT, 

Fourth Floor, East Side. 




MANUFACTURING DEPARTMENT, 

Fourth Floor, West Side. 




OUR TEMPORARY FACTORY, 

Started in Oakland four days after the San Francisco Disaster, showing the first Lietz Level 
produced within two months. This factory was kept busy until removed to our new building, 
and produced up to that time over 250 levels and transits. Such unequaled activities have been 
observed with all the various industries, demonstrating a thousand-fold that San Franciscan 
activity cannot be destroyed, even by an enormous catastrophe like the one of April 18, 1906. 




A. I,ietz Company 

Makers 
San Francisco, Cal. 



TRANSIT THEODOLITE. 



Type of instrument approved by and made for the Bureau of Engineering 
of the City of San Francisco. 




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> 



U 




A. Lietz Company 

Makers 
San Francisco, Cal. 



MINING TRANSIT, WITH INCLINED STANDARDS. 

Built to order from a special design. 




A. I,ietz Company 

Makers 
San Francisco, Cal. 



MINING TRANSIT. 

Special Features: Vertical Circle, enclosed dust proof, and graduated on the Periphery so that 
it can be read from the front; Detachable Illuminating Apparatus with 
Central Reflector inside of Telescope. 



TESTIMONIALS 



U. S. Coast and Geodetic Survey, 

Sub-Office, June 2, 1888. 
A. Lietz Co., San Francisco, Cal. : 

Gentlemen — I have your note of 1st June, asking me to express an opinion of your 
character as Mathematical Instrument makers. 

For the six years since you succeeded to the business of Carl Rahsskopff, I have been 
so well satisfied with the character of your workmanship upon the various kinds of instru- 
ments which I have intrusted to your care that I have seen no reason whatever to make 
any change. 

In the matter of new instruments and novel devices, you have fully comprehended the 
wants of the observer and have intelligently supplied them. 

Very respectfully, 

George Davidson". 



San Francisco, May 14, 1888. 
A. Lietz Co., San Francisco: 

Gentlemen — My acquaintance with your establishment for the manufacture of Nautical' 
and Field Instruments, and the knowledge I have of your excellent appliances for such- 
work, prompts me to a statement thereof, especially as you have furnished me with a sub- 
stantial proof of your workmanship in the Transit purchased of you some months ago. 
This instrument has since been constantly used in important surveys in an extremely rough 
mountainous country, and I am informed by my son, who has been operating with it, that 
it is in every respect exceedingly accurate in all operations for which a Transit is designed. 
I am glad to express my satisfaction of its results and consider it a high recommendation of 
your ability to make superior instruments. 

Respectfully yours, 

Calvin Brown, C. E. 



Berkeley, Cal., May 24, 1888. 
A. Lietz Co., San Francisco, Cal. : 

Gentlemen — Having your Transit in use, I take pleasure in expressing my satisfaction. 
I am pleased particularly with the Tripod Coupling, it saving much time. 

Respectfully, 

R. E. Bush, 

Civil Engineeer. 



San Jose, Cal., June 4, 1888. 
A. Lietz Co., San Francisco: 

Gentlemen— It is with great pleasure that we add our testimony to the excellency of 
your instruments. The two Transits and one large . Y-Level bought of you are in every 
respect as good and serviceable as the instruments made by the most reputed of Eastern firms, 
and as a purely California or home production deserve the greatest credit. 

The graduations made on your own graduating machine are clear, sharp and exact, the 
glasses of the very best make and power, and the needles much superior to the general 
run of needles. 

Your Tripod Coupling is at once simple, effective and safe, and we consider it better 
than any other coupling used by other makers. 

We can but congratulate you upon your success in the production of A No. 1 Cali- 
fornia-made instrument, and heartily recommend you to the profession. 

Very truly yours, 

Hermann Bros., 
Surveyors and Civil Engineers. 



l6 TESTIMONIALS. 

La Porte, Cal., June 5, 1888. 
A. Lietz Co., San Francisco: 

Gentlemen — I take pleasure in stating that the Mountain Transit with which you have 
provided me in April, 1887, has proved excellent. In regard to accuracy of the graduation, 
stability of tripod, reliability of instrument in its adjustments and strength combined with 
lightness, it gives entire satisfaction. 

Very respectfully, Wm. Schuld, 

U. S. Deputy Mineral Land Surveyor. 



Oahu Railway and Land Company, 

Honolulu, H. I., December 1, 1892. 
A. Lietz Co., San Francisco, Cal.: 

Gentlemen — In 1890 this Company bought one of your Transits (No. 204). It has been 
in use in a variety of work and gives excellent satisfaction. It has several improvements on 
former instruments. All the parts are conveniently arranged. The verniers are in the 
right place. 

Yours truly, C. H. Kluegel, Chief Engineer. 



Maxwell, Cal., July 15, 1891. 
A. Lietz Co., San Francisco: 

Dear Sirs — The Transit made for me by you is all that an instrument should be. It is 
almost perfect. Have used it as a level and it is as good as most 18-inch levels. 

I am now making a survey which tests its qualities very closely, and the results 
obtained are excellent. Stadia measurements of distances up to seven hundred feet fre- 
quently check within two feet. It is faster and cheaper than chaining. 

Very respectfully, 

A. J. Butler, Civil Engineer. 



San Francisco, Dec. 23, 1891. 
A. Lietz Co., San Francisco: 

Gentlemen — It gives me great pleasure to certify to the merits of Transit, No. 202, 
which I purchased from you in August, 1890. I used it on town and water works surveys, and 
found it in every respect a first-class instrument. 
Very truly yours, 

H. S. Davidson, Civil Engineer. 



Virginia, Nev., October 28, 1892. 
A. Lietz Co., San Francisco: 

Gentlemen — We take pleasure in stating that the instruments, Transits and Levels, 
which you have furnished us, have given the utmost possible satisfaction. 

The two transits have been in constant use for three years, and have proven themselves 

well adapted to mountain and underground work. They are light without weakness, and 

possess an extraordinary degree of accuracy; and, furthermore, we must acknowledge the 

promptness you have displayed in filling our sometimes imperious orders. We are, gentlemen. 

Yours very respectfully, 

Hellmann & Haist, Civil and Mining Engineers. 



San Francisco, October 29, 1892. 
A. Lietz Co., San Francisco: 

Sirs — I have used the Y-Level, No. 231, made by you, and I take great pleasure in 
stating that it has given entire satisfaction. It is absolutely accurate and in every way 
reliable. 

The same merit can be claimed by your Transits. I have used one of them for five 
months, and it is fair to state that I have never handled a better instrument. 
Yours respectfully, 

Francis Bridges, Civil Engineer. 



THE A. LIETZ COMPANY. 



17 



Aspen, Colorado, October 31, 1892. 
A. Lietz Co., San Francisco: 

Sirs — It is with great pleasure that I avail myself of the opportunity presented me to 
say a kind word for you and your work. The Transit made by you and used by me for 
the last three years, I am certain is not excelled by any other in this State or elsewhere. 

In convenience, accuracy of centering, and graduation, it leaves nothing to be desired. 
That it is today in as good a condition as when it left your shop, speaks well of its con- 
struction in other directions than accuracy alone. 

Yours truly, 

C. S. Batterman. 



Woodland, Yolo Co., Cal., November 3, 1892. 
A. Lietz Co., San Francisco: 

Sirs — Regarding Level, No. 224, which I purchased of you, I have to .say that the year 
I have owned the same has not made it a bad name. I like it even better than I did 
when I purchased it. For very accurate work in either still or windy weather I have never 
used its equal. 

Yery respectfully yours, 

P. N. Ashley, City Engineer. 



Agency Sierra Buttes Gold Mining Company, Limited, 
San Francisco, Cal., November 5, 1892. 
A. Lietz Co., San Francisco: 

Dear Sirs — I take pleasure in stating that the Level I bought of you is a first-class 
instrument, and gives perfect satisfaction. 

Yours respectfully, Wm. Johns. 



A. Lietz Co., San Francisco: 

Gentlemen — * * * * 



Wardner, Idaho, December 8, 1892. 

I prefer your instruments to any I have seen yet. 
Respectfully yours, 

Joseph P. Keane. 



Modesto Irrigation District, 
La Grange Dam, January 11, 1893. 
A. Lietz Co., San Francisco: 

Gentlemen — I take pleasure in certifying that the Transit and Level bought of you 
three years ago have given perfect satisfaction, the adjustments remaining longer than in 
any instrument I have used in twenty-five years' practice. The inverting telescopes that I 
ordered I consider superior to the erecting form, and for hard usage and accurate work 
I know of no make of instrument superior to your Company's. 
Yery truly yours, 

C. D. Rhodes, Civil Engineer. 



Clipper Mills, Butte Co., Cal., 

February 3, 1895. 
A. Lietz Co. : 

Gentlemen — You would hardly believe it, but I have used your Transit (No. 235) for 
over a year without having to adjust it, as it has retained perfect adjustment. I am very 
careful with it. 

Yours respectfully, 

H. \V. Cadwell, C. E., E. M., 
Sec. Con. Gentle Anna Mining Co. 



Eureka, Feb. 1, 1894. 
A. Lietz Co., San Francisco: 

Gentlemen — I have had the pleasure of standing behind one of your improved levels, 
and am free to say, "She's a bird." 

Yery respectfully, 

A. T. Smith, 
U. S. Deputy Surveyor. 



l8 TESTIMONIALS. 

Candelaria, Nevada, March 20, 1893. 
A. Lietz Co., San Francisco: 

Dear Sirs — I am highly pleased with my Transit, No. 254, made by you, which I have 
been using constantly for over a year. It is thoroughly reliable, and I consider it one of 
the best in use. I have had occasion to use it a great deal in long leveling practice, and 
my limit of error per mile has never exceeded one-tenth of a foot. It is a combination of 
accuracy, strength and lightness, and I can safely recommend the same in every particular 
to the engineering profession. 

Yours truly, 

John G. Booker, 
U. S. Deputy Mineral Surveyor for Nevada. 



Lake Greeno, Cal., March 27, 1893. 
A. Lietz Co., San Francisco: 

Gentlemen — Over two years ago I purchased one of your 18-inch Y-Levels. It has 
been in constant use ever since, sometimes subjected to very severe handling, and I desire 
to say that in over fifteen years' practice in the field, using instruments from most of the 
standard makers, yours is the peer of any in design, workmanship, action and all of the 
attributes of a first-class instrument. The ease of manipulation and constancy of adjust- 
ment are qualities 'possessed by it in a marked degree, and the improvements are just 
what are needed. 

In short, I would not exchange mine now for an instrument of the same grade from 
any other maker. I expect soon to lay aside all others and to use none but Lietz instruments 
in all branches of my field work covered by them. 

It is a great pleasure to me to show the good points of my level to my professional 
brothers. 

Yours respectfully, 

P. M. NORBOE, 

Civil Engineer. 



Juneau, Alaska, January 14, 1893. 
A. Lietz Co., San Francisco: 

Gentlemen — I take pleasure in stating that the Mountain Transit purchased from you 
..and used the past season has proven excellent. The graduations are clean and sharp. In 
regard to accuracy of the graduation, reliability of instrument in its adjustments — the tripod 
not only simple and safe, but always rigid — and strength combined with lightness, it proves 
^entirely satisfactory. 

Yours truly, 

Chas. W. Garside, 
\' , _ U. S. Deputy Mineral Surveyor for Alaska, and Mining Engineer. 



San Francisco, March 10, 1895. 
A. Lietz Co., San Francisco: 

Gentlemen — In the prosecution of my work in opening up the gravel mines of the Playa 
de Oro Mining Company, in Ecuador, South America, we had occasion to use one Lietz 
Transit, one Y-Level, and one Dumpy Level. 

These instruments were covered with water-proof cloth, and despite constant rain and 
exposure incident to such work, and in such a wet climate, proved thoroughly satisfactory, 
and I can most strongly recommend them. 

Very' truly, 

Mark B. Kerr 
Civil and Mining Engineer. 



Silver City, N. M., October 31, 1906. 
The A. Lietz Co., San Francisco: 

Gentlemen — * * * * * will try and place an order with you at an early date, as 
I prefer your transits for all kinds of work to those of any other make. 

Yours very truly, 

John M. Sully, 
Consulting, Mining and Mechanical Engineer. 



THE A. LIETZ COMPANY. IO, 

Silver City, N. M., February 25, 1907. 
The A. Lietz Co., San Francisco: 

Dear Sirs — I received instruments today and am delighted with same. I used a 



for eleven years and know something about Transits, and you are sure welcome to the 
price I paid. 

Thanking you for promptness and good packing, 

Yours truly, 

N. C. Titus, 
Consulting Mining Engineer. 



Downieville, Cal., February 21, 1907. 
The A. Lietz Co., San Francisco: 

Dear Sirs — I have used my new Lietz Transit two weeks now, and am much pleased 
with it. In all my twenty-two years' experience with Transits, I have never handled a 
more satisfactory instrument. 

Yours truly, 

Geo. F. Taylor, 

Civil Engineer. 



Clio, Plumas County, Cal., May 4, 1907. 
The A. Lietz Co., San Francisco: 

Gentlemen — We have a number of your Transits and Levels in use on the construction 
of the Western Pacific Railway through the Sierra Nevada Mountains, both for tunnel 
work and outside work, and all the men prefer them, in consequence of which, in ordering I 
always specify your make. 

Yours truly, 

J. Q. Jamieson, 
Division Engineer. 



Ithaca, N. Y., May 9, 1907. 
The A. Lietz Co., San Francisco: 

Gentlemen — * * * * * will say that the Transit purchased of you last year appears 
to be of first-class workmanship. It has given entire satisfaction and is placed among our 
best instruments. 

Very respectfully, 

C. L. Crandall, 
College of Civil Engineering, Cornell University. 



Calexico, California, May 2, 1907. 
The A. Lietz Co., San Francisco: 

Dear Sirs — The small Transit you sent us recently has given entire satisfaction. 

Yours truly, 

F. C. Hermann, 
Chief Engineer, California Development Co. 



Fairbanks, Alaska, November 23, 1906. 
The A. Lietz Co., San Francisco: 

Dear Sir — The Mining Transit, No. 9, Aluminum, purchased of you last March, gives 
good satisfaction, and for precision and all-around work I have never seen its superior. 
With best wishes for your future success, I remain, 

Yours very truly, 

L. S. Robe, 
Civil and Mining Engineer. 



ALUMINUM INSTRUMENT TESTIMONIALS 



San Jose, Cal., April 14, 1895. 
A. Lietz Co.: 

Gentlemen — We have used one of your Aluminum Mountain Transits for nearly a year, 
for all kinds of engineering work, in places exposed to great heat and strong winds, and find 
that it gives us better results and more satisfaction than heavy transits of brass. 

We find that its small weight allows an easier and quicker handling in rough, mountain- 
ous places, and also keeps the instrument in better adjustment and more free from accidents. 
In fact, we don't see how we got along so far without it, and why engineers and surveyors, 
who have a great deal of mountain work to do and carry their own instrument, insist upon 
breaking their backs with a 25-pound instrument, when they can get one which weighs 7 
pounds, and does the work fully as well. 

Respectfully yours, 

Herrmann Brothers, 
Surveyors and Civil Engineers. 



The Mineral Farm Consolidated Mining Co., 

Aspen, Colorado, April 30, 1895. 
A. Lietz Co.: 

Dear Sirs — I have been using for several months a Transit of your make, having inclined 
standards. 

The standards and telescope are of your aluminum alloy, and give perfect satisfaction, as 
does the entire instrument, which is of special make throughout. This makes two Transits of 
your manufacture that I have used. 

Yours truly, 

C. S. Batterman, 

Manager. 



San Francisco, May 7, 1895. 
A. Lietz Co.: 

Dear Sirs — Your small Aluminum Transit, No. 342, proves to be for my purposes the 
most convenient and satisfactory instrument I have yet had in use. 

It is well constructed and large enough for all ordinary underground and surface surveys, 
and being very light is particularly handy for rapid work. 

Yours truly, 

Ross E. Browne, 
Mining and Llydraulic Engineer. 



University of California, 
Department of Civil Engineering and Astronomy. 
Berkeley, May 10, 1895. 
A. Lietz Co., San Francisco: 

Gentlemen — The Plane-Table Alidade made by you for the University several years ago 
has always given satisfaction. 

We have instruments made by several of the first-class makers in this country, and your 
Alidade compares very favorably with these. 

Very respectfully, 

H. I. Randall, 
Instructor in Civil Engineering, LTniversity of California. 



THE A. LIETZ COMPANY. 21 

Ferndale, Cal., May 15, 1895. 
A. Lietz Co., 422 Sacramento St., San Francisco: 

Dear Sirs — I desire to state that I am well pleased with your small Aluminum Transit, 
which I purchased from you about two years ago. It is small, light and accurate. Being light 
it is particularly adapted for mountain field work. 

There is no question but that the Aluminum Transit is the one for the engineer, as it com- 
bines accuracy with lightness. 

Yours respectfully, 

J. A. Shaw, 
Civil Engineer and State Licensed Surveyor. 



Board of State Harbor Commissioners, 
No. 10 California St. 
San Francisco, May 29, 1895. 
A. Lietz Co.: 

Gentlemen — With regard to the Aluminum Y-Level, No. 304, made by your Company for 
the Board of State Harbor Commissioners, I take pleasure in informing you that it has given 
perfect satisfaction, and I will state that if it were not possible otherwise than by paying 
double the price of the old-style brass instrument, I would willingly do so in order to get one 
of aluminum manufacture. 

One only has to use such an instrument for a day to appreciate the difference. 
As to the workmanship of the above level, I have never seen better in my experience as 
an engineer. 

Yours respectfully, 

Howard C. Holmes, 

Chief Engineer. 



County Surveyor's Office, Santa Cruz County. 
Santa Cruz, Cal., June 1, 1895. 
A. Lietz Co., San Francisco: 

Gentlemen — I take great pleasure in informing you that I have used the Aluminum 
Transit, No. 320, made for me by your firm about a year ago, on all kinds of city and county 
work, and find it in every way the equal of any old style (bronze) instrument I have ever 
used. 

It holds its adjustments very well, and is as steady in the wind as any of the heavier 
instruments, while the saving of labor in carrying it is a gain that cannot be over-estimated. 
I think that when it has been once thoroughly tested by any engineer, he will abandon his old 
instrument in its favor in every instance. 

The graduations and workmanship are in all respects excellent. 

Yours truly, 

Chas. L. Pioda, 

City Engineer. 



San Francisco, Sept. 6, 1894. 

I have had occasion to use a small Aluminum Transit, weighing 4^ pounds, continuously 
for about six months, and during that time I made it a point to use it in very severe and 
stormy weather. 

I recall a very strong breeze near a California mountain town, when the local engineer of 
the work, upon which I was then engaged, and I were operating together, he with a large 
Transit weighing iy]/ 2 pounds, without the tripod. Although my instrument trembled, its 
motion was not a violent one, and I could still read a stadia rod at 400 feet distant, when it 
was utterly impossible for him to manage his heavy instrument at all. The amplitude of its 
vibrations was longer, and its larger superficial area gave the wind more surface to act upon. 
Whenever there was a lull in the wind, my Transit would stop trembling at once, while the 
heavy instrument would continue shaking until the next gust would strike it again. 

It was proven to our satisfaction that the small Aluminum Transit was by far steadier 
than the large instrument, although the latter exceeded it 13 pounds in weight; it was not 
as top-heavy and the wind had less effect upon it. 

The local engineer referred to, who had had quite an objection to a 4^-pound Transit, 
became fully converted to aluminum instruments after our first mutual experience in the 
wind, and is today as firm a believer in this metal as I am myself. 

Otto von Geldern. 



22 TESTIMONIALS. 

Mountain Home, Elmore Co., Idaho, May 5, 1894. 
The A. Lietz Company, 422 Sacramento Street, 

San Francisco, Cal. : 

Gentlemen — The instruments ordered (Aluminum Transit and Level) came to hand in 
due course of time all O. K., and I have neglected writing you on account of press of busi- 
ness and wanting to have an opportunity to test the transit in different ways. 

What can I say in praise of the same? Words are useless. Money could not buy them 
if I could not replace the same. I think that will give you an idea of my appreciation of 
your instruments. 

The objection was raised by several engineers that the Transit would shake in heavy 
wind. I know better, and experience is the best of knowledge. Example: Having a placer 
claim to survey, situated upon a low flat island in Snake River, I crossed the island when the 
waves were rolling about three feet high, and each roller helped to make it uncomfortable by 
washing into the boat; commenced at lower end of island, stake No. 1, and ran around 
the island sixteen courses and angle corners, and closed within three feet on stake No. 1, by 
calculation Lat. & Dept. Area 93 acres. Now any instrument that will do such work as 
that in a windy day on Snake River (and just knows how it blows there), I think is beyond 
criticism. 

Having many levels to run, I have used the Telescope for running the same on one 
of our canal lines. Preliminary survey. Ran south on Twp. line, and at 700 ft. set 
stake on lower side of ravine. Returned • to starting point and ran south-easterly, crossed 
ravine in narrow place for flume, and ran down south bank of ravine to stake at 700 ft. and 
closed; looked at other paper on which I had taken levels on Twp. line and found that 
readings were same for that point. Elevation 9.40 ft. Such an instrument will answer 
for me; those who want a better one can hunt for it. 

The level is a Daisy and meets all requirements. 

An engineer or surveyor can carry it all day and not feel like leaving it where he stops 
at night. I would recommend the same to any one of my profession, and advise them to 
go and do as I did: Buy the same from A. Lietz Company. 

Yours respectfully, 

Samuel G. Rhodes, 
U. S. Dep't Surveyor for Idaho. 



Port Chester, N. Y., Feb. 10, 1904. 

Gentlemen — The Aluminum Transit Theodolite made for me by your firm seven years 
ago has proven to be a most satisfactory instrument. 

It has been in use almost continuously these years on all kinds of work met in the gen- 
eral, practice of a civil engineer, has had rough usage, but escaped serious injury, and has not 
once been to the makers for repairs. 

I have heard objections urged against the use of aluminum in mathematical instruments, 
the fear being expressed that the metal would not meet the requirements of surveying instru- 
ments particularly. 

My experience has proven such objection groundless, for notwithstanding the seven 
years' usage given this instrument by myself and assistants, it shows no indication of wear or 
fatigue, and gives promise of a long life of usefulness. 

I would add that I believe the staunchness of the instrument in question is due in a large 
measure to the design of which the essential features are the strong, single centre and "U"- 
shaped standards cast in one piece, these wrought by skillful workmanship and furnished 
with one of the best divided circles, complete an instrument that for accuracy, strength and 
lightness is rarely equaled. Very respectfully yours, 

F. S. Odell. 



San Francisco, California, July 19, 1904. 
The A. Lietz Company, 422 Sacramento Street, San Francisco, Cal.: 

Sirs — It affords me great pleasure to testify to the merit of an Aluminum Transit, your 
small instrument, No. 9, which I have had for over eight years, which has accompanied me on 
long voyages, has been exposed to extremes of climate, to rough handling in all sorts of trans- 
portation, and yet has never failed to do excellent and absolutely reliable work. 

The light metal was chosen because it was an object to me in my hazardous travels to 
reduce the weight of my outfit as much as possible, and a Transit weighing but little over five 
pounds with its box became an item of inestimable value to me. 

This little instrument has had many adventurous mishaps, but it has never lost its 
usefulness, and is as trustworthy today as when first bought. 

Some years ago, while in Siberia, an accident happened to our boat while journeying on 
a river, and the instrument fell into the water. It was recovered after a considerable effort, 
but it had suffered no injury. From the rigorous climate of Siberia it was taken to the 
Argentine Republic, under climatic conditions entirely different, yet it did its work as well 
there as in Siberia. 

It underwent a similar change by taking it to the Klondyke, where it had the misfortune 
to fall from a second-story window, and yet it did not suffer sufficiently to prevent me from 
completing my work. It has become a Transit with a history, and I have learned to appreciate 
the very excellent qualities it possesses. It is light, rigid, firm, tough and extremely well 
constructed, compact, with proper dispositions for work that I have to do with it. 

I realize that aluminum is the proper metal for the universal instrument, that is for an 
instrument called upon to do any engineering work in any climate, under very trying con- 
ditions, where it is impossible to devote that attention to its safety that under ordinary 
conditions, with every facility and assistance, is expected to be given to a delicate tool. 

I take great pleasure in recommending such instruments to the profession. You have 
skillfully, intelligently and conscientiously made for me an article that I have every reason 
to appreciate very much. Yours very truly, 

Chas. F. Hoffmann, 




m 

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CAUTION 



In order to prevent changes in the magnetism of the Needle, do 
not bring your transit instrument into juxtaposition with objects gener- 
ating or transmitting strong electric currents, such as dynamos, electric 
car lines, etc. If absolutely necessary to be within the influence of 
strong currents, allow the needle to swing freely. Avoid riding in 
electric cars with your transit, if possible. 



Description of Instruments 



MANUFACTURED BY 



THE A. LIETZ COMPANY 

SAN FRANCISCO, U. S. A. 

With Remarks on their proper Use, Care, Preservation 

and Adjustments. 



Description of the Lietz Instruments 

Including Remarks on their Use, Handling, Care, 
Preservation and Adjustments. 



THE ENGINEERS' TRANSIT OR THEODOLITE. 

In reviewing the different parts of the transit and theodolite, it 
will answer our purpose to include them, for the present, under one 
head, using both terms as synonymous — The word theodolite having 
been defined as an instrument of angular measure, possessing two 
graduated circles, normal to each other, which during manipulation 
are set in horizontal and vertical planes respectively. Bauernfeind says 
that it is generally believed that the word theodolite (theodolith) is a 
combination of Sea sight, oSos road, and Ai#os stone. He says that 
in order to understand this derivation it must be known that formerly 
all supports upon which theodolites were placed were made of stone. 
This meaning, however, seems somewhat ambiguous, and other deri- 
vations have been sought. The etymology of the word is uncertain. 

In classifying there appear two distinct groups of theodolites : the 
simple theodolite, in which the lower clamp and tangential movement 
is neglected; and the repeating theodolite, possessing the double hori- 
zontal movement on spindle and plate, which is the principal feature 
of all complete field instruments made for the engineer at the present 
time. A combination of the two types is the Cyclotomic Transit, which 
will be fully described in this Manual. 

The various parts of the transit or theodolite may be grouped 
under the following heads, viz. : 

Beginning from the base-plate we have : 

i — The tripod connection with the leveling, plumbing and center- 
ing apparatus ; 
2 — The centers ; 

3 — The graduated plate and verniers ; 
4 — The compass and variation plate; 

5 — The standards with the vertical arc and its movements ; 
6 — The gradienter ; 
7 — The spirit levels ; 
8 — The telescope. 



THE A. LIETZ COMPANY. 2"] 

i. The Tripod Connection. 

An important feature of the Lietz instruments is that they are 
attached to the tripod by a friction coupling. 

It has been customary to accomplish this, heretofore, in two differ- 
ent ways. One is to attach the instrument to the tripod by means of 
a screw at the base-plate, whereby it remains complete in all its parts 
and is never separated above the leveling screws. This is the method 
employed by the best makers, but it is somewhat tedious and unsafe, 
as every engineer has had occasion to find out. It is often the case 
that the screw will not catch, and there is always a loss of time and 
patience in trying to enter the thread properly. Another point is that 
while turning it on, the entire weight of the instrument rests upon the 
screw thread, with a constant tendency to wear it away. 

The second method of fastening the transit to the tripod is by 
means of the center, making it attachable or detachable above the 
leveling screws. In most cases the foot screws may also be turned 
from the tripod head, but it is not unusual to have them remain as a 
fixed part of it. This mode of coupling seems to us very defective. 
The exposed center is liable to injury in many ways. Dust particles 
accumulate, and it moves with difficulty in consequence, if it does not 
cause fretting. But its greatest fault is the incumbent necessity of 
providing for it what is called the Hat center, for turning the upper 
plate. In such an instrument the plates stand too high above the level- 
ing screws, which causes unsteadiness. We believe it to be very 
difficult, if not impossible, to do accurate work with such an instru- 
ment, to which point we shall refer again hereafter. 

These substantial reasons have caused Mr. Lietz to invent a new 
tripod coupling, which is regarded as the most successful innovation 
by all who have had occasion to use it. 

Figure I fully illustrates this simple but most effectual device. 

On the tripod head, instead of the ordinary screw, there are 
three jaws. The base plate of the instrument is swallowtail-shaped on 
the inside (as shown at F), and is provided with the spring case C*. 
The coupling of the two is done by letting one of the grooves on the 
base plate meet any one of the jaws on the tripod head, when one- 
third of a revolution to the right will make the connection ; at the 
same instant the spring C will fall into a hole in the base-plate, which 
thus prevents any possible disconnection; the latter is effected by lift- 



* The spring C in the latest construction is now placed on the tripod head, between 
the lugs. 



28 MODERN SURVEYING INSTRUMENTS. 

ing the spring C and turning to the left. If the tripod head should 
have been worn or bent by accident, the movable jaw D, which. is 
worked by the side-screw E (with a large adjusting pin), will again 
give the coupling friction enough to hold the instrument perfectly firm 
on the tripod. 




Figure I. 

The chief merit of our arrangement is that it enables one to attach 
or detach the instrument to or from its tripod more rapidly, firmly and 
safely than by any other device so far known, and that, too, 
without dividing the instrument proper into two parts, which is 
always injurious to its accuracy and stability, as we have just pointed 
out. To this we may add that it is more durable, easier to keep clean 
and cannot get out of repair. 

The movable jaw, once set for the instrument, need not again be 
interfered with. It is absolutely needless to adjust the friction every 
time the instrument is placed on the tripod. 

We feel quite confident in saying that every engineer who has 
once used this new coupling will readily detect its great merits, and 
will never be without it. All the large-sized transits and levels of the 
Lietz make fit the same tripod head, and are instantly adjusted. 

a. Leveling Screws. 

As these are used more than any other part of the instrument, 
it is evident that they should be very durable. Those of the Lietz 



THE A. LIETZ COMPANY. 20, 

make possess a very deep thread, rounded a little on the edge, which 
insures a very smooth motion and greater durability than sharp-edged 
threads. The screws are made of composition metal. 

The lower construction of the transit is made with the view of 
affording the greatest steadiness under all conditions. For that rea- 
son the leveling screws are not run through a thin metal disc, with a 
common nut attached for their operation, but an extra strong, star- 
shaped casting, made in one piece, is provided, through which the 
screws are passed and in which they operate. 

The whole construction of this part is intended to insure the abso- 
lute steadiness of the instrument, and to give it rigidity even in a 
strong wind. Any other construction, with a light disc parallel to the 
base-plate, cannot afford that stability which a first-class transit or level 
should possess ; and, since this is one of the prerequisites of an instru- 
ment of precision, we have laid particular stress upon our leveling 
arrangement, which is of the most approved modern design. 

For instruments of the greatest precision, as those used in triangu- 
lation or geodetic work, it may be an advantage to arrange the base 
with three leveling screws instead of four. These changes will always 
be made upon application. While the ordinary complete transit is more 
compact and of greater utility with four screws, in a specially 
designed instrument for the finest work it will always be well to con- 
sider the advantages of the three-screw system, universally adopted 
in European instruments. 

b. Shifting Center for Facilitating Plumbing and Centering. 

All our complete instruments are furnished with shifting plates for 
the purpose of setting them precisely over a point, after having approxi- 
mately done so by the tripod legs. This arrangement is of the greatest, 
utility to the field man, and we are convinced that those who have 
adopted it will never again dispense with it. 

While it does not make the instrument less rigid or portable, it 
is so easily manipulated, and becomes a great labor-saving factor. In 
order to center the instrument accurately, two of the leveling screws, 
require a slight loosening, when the transit may be shifted upon the- 
tripod until the center of the plumb-bob is directly over the point to 
be occupied. The screws are then turned down and the instrument 
leveled up in the usual manner, when it will stand as firm upon its 
base as required. 



30 MODERN SURVEYING INSTRUMENTS. 

2. The Centers. 

In manufacturing this all-important feature, the very backbone 
of the instrument, too much care and attention cannot be bestowed. 

It is essential that both of these metal axes should have the same 
absolute center as the graduated plate and the horizontal telescope axis, 
whichever way the instrument may be turned. This is accomplished 
by the A. Lietz Company by making this detail a specialty. The care- 
fully chosen material for the vertical axes, the exact method of turning 
and fitting them, and the precision reached in the manner of center- 
ing them, together with the subsequent scrutinizing test to deter- 
mine the slightest eccentricity, have accomplished results as per- 
fect as mechanical means and human ingenuity can achieve. 

Eccentricity has been a source of annoyance and error to the 
engineer, to determine which a number of practical methods have been 
invented and put to use. One of the most ingenious has been inserted 
in this catalogue, which will be found in full elsewhere. 

But with our modern transit, if used with ordinary care, this 
source of error has been eliminated, or at least reduced to the lowest 
possible minimum. 

The length of our centers is from 2^4 to 4 inches, according to 
size and style of instrument. To our best belief, this is more than the 
instruments of any of the many different makers possess, having con- 
stantly handled a great many of them in repairing. Yet, by examining 
our illustrations, it will be noticed that with us the limb and vernier 
plates are nearer to the tripod head than in those of other make, owing 
to the judicious placing of the centers, which reach down into the 
base, thus insuring the utmost stability. By comparing our cuts with 
those in other catalogues, the reader will obtain a pretty fair idea of 
what we mean to impress upon him — such a comparison being better 
than any argument by either ourselves or others, based upon mere 
assertion. 

Examine carefully our construction of the centers, and you will 
be soon convinced that our claim for rigidity and stability is fully 
warranted. 

3. The Graduated Plate. 

We have now come to the most essential part — the very soul of 
the instrument. It is needless to dwell upon the necessity of an accu- 
rate graduation; it is self-evident, and it becomes the instrument- 
maker's pride to make it so. 

We guarantee our work in this particular as perfectly reliable, 
the graduation lines straight, thoroughly black and of uniform width. 



THE A. LIETZ COMPANY. 3 1 

The plate is accurately centered and free from eccentricity, as 
already explained. 

The horizontal circle is graduated from o to 360 degrees, with 
two sets of figures running in opposite directions (unless ordered 
differently). They are large and distinct, and, to avoid errors in read- 
ing, the figures of these two sets, and those on their corresponding 
verniers, are inclined on opposing slants, thus indicating the direction 
in which the vernier should be read. 

We recommend graduations on a solid silver ring, as that metal 
offers many advantages for the purpose — in fact, its great permanency 
and smoothness renders it the only satisfactory surface for fine gradu- 
ations. However, they are made as the customer desires ; but since 
the additional outlay for silver graduation is only $10, we seldom have 
any difficulty in impressing the purchaser with its advantages. 

It is customary with us to graduate circles so that they may be 
read to single minutes or thirty seconds of arc. We make any 
degree of refinement called for, but our manufactured goods are always 
on hand in the two vernier divisions named. 

a. The Vernier. 

This consists of a small sliding scale, movable upon a larger one, 
so graduated that n parts thereof shall include either n -\- 1, or n — 1 
parts of the larger scale. The scale may be applied to either straight 
lines or arcs, and aids to determine the smaller divisions of measure 
between the lines on the larger scale. 

A tedious method for measuring small values of arc by means of 
concentric circles was given in the early part of the sixteenth century 
by a Portuguese, Pero Nunez (Nonius), and after him the name of 
nonius is still applied in Germany and other countries to what we 
exclusively call a vernier here. This term was justly given it in honor 
of the Dutch captain, Peter Werner, who gave to the scale the sliding 
shape in which we now apply and use it practically. Signing himself 
"Pierre Vernier" in a discussion of the "Nonius," written by the 
inventor in the French language and published in Brussels in 1631, 
gave rise to the term we now almost universally employ. 

The graduations on a vernier are usually so made that n divisions 
thereof shall equal n — 1 divisions on the circle. 

It becomes a simple problem to determine the value of n from the 
following equation : 



32 MODERN SURVEYING INSTRUMENTS. 

Let / = length of one division on circle, 

/ 1 == length of a vernier division, it is evident that 
/ (n — i) =l t n, or 



»=7=f 

The value of any quantity in the equation may then be readily 

expressed in terms of the other ; / — l lf or the smallest readable divis- 

/ 
ion, being equal to — • 

It is customary to graduate the circles of the Lietz transits in 

20-minute divisions, reading to either 20 or 30 seconds on the vernier. 

20X60 

The value of n in these cases is - — , or 60 in the former, and 

20 

20 X 60 

5 or 40 in the latter ; or, in other words, 59 and 39 divisions on 

o 
the circle will correspond to 60 and 40 on the vernier respectively. 
Instruments reading to one minute of arc are divided to 30 minutes on 
the plate ; in that case 29 circle spaces are equal to 30 vernier spaces. 

Every good instrument should have two verniers ; they should be 
covered with glass to protect them from exposure-, and for ease in 
reading they should be provided with ground glass shades. 

Our verniers are in such position that the observer need not step 
aside in order to read them, for we place them about 30 degrees from 
the line of collimation. The method of thus placing them has been 
pronounced objectionable, because the size of the plate level, which is 
at right angles to the line of collimation, and the more important of the 
two, has to be reduced. By examining our instruments, however, 
any one will see that we have attained the object without reducing 
its length, without placing it over the vernier, and without allowing 
it to extend materially beyond the circumference of the plate — all of 
which would be objectionable features. 

The space between the circle and the vernier must appear, through 
a magnifying glass, like a fine black line. No accurate reading can 
be taken if the space appears wider than a mere line of uniform 
thickness under the revolution of the plate. 

b. Clamp and Tangent Screws. 

The lower clamp screw of our transit is of the best devised shape 
and arrangement. It is strong and rigid, and answers the slightest 
touch. 



THE A. LIETZ COMPANY. $$ 

The upper clamp does not come in contact with the limb, but grasps 
the sleeve of the outside center. This is far preferable to the old 
method of pressing together the two plates by means of a screw placed 
at some point on the circumference. ' 

The tangent screws are single only, and operate in metal cases 
against opposing springs. Great care has been bestowed in eliminating 
all lost motion of these screws. We consider double tangent screws, 
working against a tongue, as entirely obsolete. Any instrument sold 
today with double opposing tangent screws may be set down as anti- 
quated and behind the times. It is absolutely necessary that every- 
thing tending to create lost motion must be carefully avoided. While 
adjusting the line of collimation, this source of error becomes very 
annoying, for, in revolving the telescope, the plate is liable to turn 
slightly and the operator is never sure whether the cross-hairs are in 
adjustment or not. 

The arrangement of our tangent screws combine simplicity with 
absolute reliability. Being single, they require but one hand in manipu- 
lation, and their judicious location and spring case arrangement make 
them active and operative at any instant. 

4. The Compass. 

Our needle differs somewhat in shape from others, being a little 
smaller in the center than towards the ends, for the reason that the 
magnetic influence is manifested at the ends only, so that all the central 
metal may be called dead weight. Compared with those of other 
makers, the Lietz needle is, therefore, a little lighter, which conditions 
the increased durability of the point upon which it poises. 

Hard steel has the capacity of retaining magnetism longer and 
better than when tempered, and for that reason we have adopted the 
plan of leaving one-half inch on both ends perfectly hard. 

The closest attention is given to the center cap — which contains 
an agate setting — and to the pin upon which the needle rests, for the 
accuracy or sensitiveness depends principally upon these two details. 
These needles possess that degree of sensitiveness required in a high- 
grade instrument. A sluggish needle — one that will hang like a dead 
load — is not fit for the observation of a reliable azimuth. 

The center pin must occupy the true center of the graduated circle, 
and must stand normal to its plane. We utilize precise instruments 
with high magnifying power to obtain the absolute true position of 
the pin, in order to avoid all errors due to eccentricity. 

The lifting arrangement is applied with the view of raising and 



34 MODERN SURVEYING INSTRUMENTS. 

lowering the needle gently and gradually, as any sudden drop to the 
pin, or any quick action of arresting its motion, is sure to cause a 
rapid wearing of the point and the cap. 

The Compass is divided into 30-minute divisions, and numbered 
from o to 90 degrees in each quadrant from the north and south points. 
This is done to conform with the usual practice of surveyors in this 
country to record bearings in the four quadrants. But any desired 
method of numbering the compass, either from o to 180 degrees, or 
from o to 360 degrees, may be had upon application. 

In order to record at once the true bearings in the field, instead 
of the magnetic, the instrument can be provided with a variation plate, 
i. e., an arrangement for laying off the local deviation of the needle 
by a movement of the graduated compass ring, so that the indicated 
course of a line shall show at once its relation to the true meridian. It 
is so made that the variation may be laid off with precision to the 
minute, by the aid of the instrument's vernier. 

This is done in the following manner : 

Having set the plate vernier to zero, adjust the instrument and, 
with the aid of a good reading glass, place it in such a direction that 
the north end of the needle shall point to the zero of the compass ring, 
which latter must coincide with the little pointer provided for that 
purpose. Having carefully set the instrument thusly by means of the 
lower clamp and its tangent screw, which can certainly be done to the 
nearest minute of arc, we release the clamp of the plate and proceed 
to lay off the amount of the local deviation of the needle in degrees 
and minutes by means of the plate-vernier — to the left if the variation 
be east. The instrument is now again in a fixed position, the telescope 
pointing to the true north, or as much to the left of the needle as the 
magnetic variation is east. We now insert the small phosphor-bronze 
pin supplied for that purpose on the side of the compass ring, and 
proceed to turn the ring until its zero shall coincide exactly with the 
north end of the needle, when every subsequent reading of the com- 
pass, in any position, will indicate the bearing of the vertical telescope 
axis from the true meridian. 

This simple little device is fully up to the standard of accuracy 
required, for with care in setting the needle we can always obtain 
results correct within the nearest minute. We find that by this method 
the additional vernier, usually placed inside of the compass ring, be- 
comes superfluous, as the plate and vernier of the transit are perfectly 
capable of taking care of the duties of this unnecessary accessory. 

The variation plate has proven a great labor-saving device, as the 



THE A. LIETZ COMPANY. 35 

observed courses require no reduction to the true meridian subsequently. 
It is now almost universally called for; and for those practitioners 
with whom land surveying is a specialty we should, by all means, 
recommend it as an indispensable feature. 

5. The Standards and Vertical Arc. 

The standards are so constructed as to give the maximum support 
to the telescope, commensurate with the size of the plate. They are 
light, but rigid and strong. 

To avoid unequal expansion of the metal in the standards by 
exposure in the hot sun, which has a tendency to elevate one end of the 
telescope axis and to depress the other, vitiating the adjustment, they 
are now what is called cloth-finished. This finish, being a non-con- 
ductor of heat, reduces to a minimum this source of possible error, 
which, in very sensitive instruments, is of sufficient moment to be 
guarded against. Other parts of our instruments are also finished 
in the same manner, particularly Level telescopes, which we shall have 
reason to mention again hereafter. 

The bearings for the telescope axis are made with extra care and 
attention. 

The axes of the Lietz transit telescopes are cut to conical bearings, 
which is a feature altogether preferable to the corrugated shape fre- 
quently found in surveying instruments. The advantage of the former 
is very evident, in that there is less friction than by any other contact ; 
and, in addition to that, it affords a much finer fitting by reason of its 
conical shape. But it is very essential that the hardest metal should be 
used for this purpose, as a material of insufficient hardness would soon 
wear, and the axes would become elliptical. 

One of the standards is supplied with an adjusting device to 
regulate any inaccuracy in the motion of the telescope in the true verti- 
cal plane, when the centers of the instrument stand vertically. 

One standard carries the arc for observing vertical angles, which 
may be either a full or a half-circle, as the customer desires. It is 
usually made to read to minutes, but may be graduated finer if so 
ordered. A clamp and tangent screw are provided on the right-hand 
standard, which are made like those already described for the hori- 
zontal movement. Every part of the vertical measuring apparatus is 
strongly and accurately made and fitted, to insure the best results in 
its practical application. 



36 MODERN SURVEYING INSTRUMENTS. 

6. The Gradienter. 

The head of the tangent screw of the vertical arc movement is 
made somewhat larger, properly silvered and graduated into a number 
of equal parts on its circumference, the thread of the screw being cut 
with great precision, so that its revolution may be accurately recorded 
by the divisions of the micrometer head. 

One complete revolution of the screw corresponds to 5 / 10 of a foot 
of difference in level in 100 feet. Since the head is divided into fifty 
parts, it follows that one division equals a difference of 1 / 100 of a foot 
in 100 feet. 

With this attachment grades may be established very quickly. It 
is only necessary to set the screw head to zero, level and clamp the 
telescope, and turn the screw up or down as many spaces as there are 
hundredths of a foot of rise or fall in one hundred feet of the grade 
to be laid out. With the small scale over the screw thrown back, the 
gradienter is used as an ordinary tangent screw. It is one of the most 
useful accessories, is easily applied, and adds nothing to the weight of 
the instrument. 

This attachment is also useful in the determination of horizontal 
distances, it being obvious that the difference in rod reading between 
two complete revolutions of the screw will indicate at once the distance 
of the rod from the observer. Where the ground is level, or nearly so, 
the simple difference in rod reading will suffice; but when this is not 
the case, the necessary corrections will have to be applied to obtain the 
true horizontal distance. 

7. The Spirit Levels. 

We have already noted that for our purposes we import the very 
best article obtainable in Europe. 

An instrument of precision, capable of measuring delicate differ- 
ences, requires delicate and sensitive levels. This is so obvious that we 
ought not to call attention to it here, were it not for the fact that we 
are frequently approached by surveyors who wish to impress upon 
us the idea that this or that make of instrument met with their approval 
because its bubbles would stay in place when once adjusted. For this 
reason we want to repeat that it is no claim for superiority of a spirit 
level because it works sluggishly. An engineer in the field must know 
when his instrument is absolutely level, and its bubbles should indicate 
to him at once when this is not the case. If they do not do so, then 
the instrument does not come up to the required standard of a precise 
tool. It would hardly do to place a carpenter's level on a transit, yet 



1 



THE A. LIETZ COMPANY. 37 

we have no doubt that its excellent qualities of remaining stationary 
would find admirers. 

Remember, also, that sluggish levels are cheaper, and that it is 
not to the instrument-maker's financial benefit to put in a delicate and, 
therefore, much more costly article. 

There is, of course, a limit to the degree of sensitiveness, and that 
we never exceed, adapting it in all cases to the work demanded of the 
particular instrument in hand. 

Our levels are ground to the proper curvature, and each is care- 
fully tested upon our level tester before it is attached anywhere.* 

8. The Telescope. 

We have now reached another most essential feature of the instru- 
ment — that which may be compared to the head of the body, containing 
the delicate organ of sight — the lens. 

a. The Lenses. 

We have already called attention to the fact that our optical acces- 
sories are imported from Europe, and that we take great pains to 
obtain the best article for the purpose. 

Without going into the detail of optical mathematics and formulae, 
that can be readily found in any text-book on physics, we all know that 
it has been the constant aim to produce lenses as free from spherical 
and chromatic aberration as it is possible to make them. The lenses 
of the Lietz telescopes are of the celebrated Jena glass — an achievement 
in theoretical and practical science of which it would be interesting 
to make some explanation here. 

The Jena Glass Works. 

The far-famed glass melting works for optical and scientific pur- 
poses of Schott and Associates, in Jena, was founded in 1884 by men 
who were of eminent scientific attainments, and who based the mag- 
nificent industry upon long continued research in this particular field. 
Our information comes from a short description furnished by the 
leading men of the enterprise, which was published some time ago in 
connection with a list of the glass varieties manufactured. 

The industry originated from a series of scientific investigations 
made for the purpose of determining, from their chemical combina- 
tions, the resulting optical properties of fusible compositions having 
an amorphous congelation. These experiments were undertaken by 

* The telescope may be furnished with a reversible level. 



38 MODERN SURVEYING INSTRUMENTS. 

Professor Abbe and Dr. Schott, to obtain information regarding the 
chemical and physical principles underlying the manufacture of optical 
glass. This work began in January, 1881, and was prosecuted in 
accordance with a prearranged plan in such wise: that Dr. Schott 
made the necessary melting tests at his home in Witten, while the 
optical investigations of the samples obtained were carried on in Jena 
by Professor Abbe, or his assistant, Dr. Riedel, by means of spectro- 
scopic analysis. 

The melting tests were made at that time on a very small scale 
(not over 300 to 900 grains in bulk), and were solely directed to the 
one object of studying carefully the influences of all chemical elements 
that may possibly obtain in any form in amorphous fusible composi- 
tions, upon the power of refraction and dispersion in their manifold 
combinations. 

By carefully continuing the investigations in this manner to the 
end of the year 1881, a number of facts and data had been collected 
regarding the specific optical effect of certain masses, which gave 
promise of new glass combinations that, for certain purposes, would 
possess more advantageous characteristics than those offered by the 
ordinary crown and flint. 

In order to utilize these results in practical optics as much as 
possible, it was decided to continue the work on a new plan, and that 
was : to combine systematically glass fusions on the optic-chemical 
principles established by the preceding experiments that should possess, 
as far as possible, all the desirable optical properties, together with other 
physical qualities fitting them specially for practical use, such as 
hardness, unchangeableness, freedom for color, etc. 

With this end in view, Dr. Schott removed his residence to Jena 
in the spring of 1882, where a special laboratory, with every facility 
for melting, was fitted up in a building rented for the purpose. 

With the aid of gas furnaces and modern blowing apparatus, it 
became possible to make melting tests on an amply large scale, up to 
quantities of about 25 pounds. 

With the assistance of another chemist for the analytical investi- 
gations, which had to be carried on simultaneously with the synthetical 
work, and one workman, the tests were continued in this laboratory 
until the end of the year 1883, whereby two special lines of investiga- 
tion were closely followed, which practical optics had laid out as the 
principal directions of research. 

The first problem considered the making of crown and flint glass 
couples, possessing as near as possible a proportional dispersion in the 



THE A. LIETZ COMPANY. 39 

various sections of the spectrum, for the purpose of obtaining a higher 
degree of achromatism than had heretofore been possible by employing 
the usual optical glass ; that is, it was sought to obviate, or to reduce 
the very considerable secondary aberration, which the silicate glasses 
still permit in all their achromatic combinations, and which is due to 
the disproportionate dispersive powers in crown and flint. 

The second problem — considered of no less importance, although 
the subject involved had, generally speaking, not been deemed a 
necessary feature in optics up to that time — consisted in obtaining 
a greater variety of gradations or modifications of the two principal 
constants in optical glasses, viz. : the exponent of refraction and the 
mean dispersion. 

The silicate glasses in use at that time, true to the simplicity and 
uniformity of their chemical constituents, show images of a simple 
series in which, ascending from the lightest crown to the heaviest flint, 
the dispersion increases in the same measure as the exponent of 
refraction increases, up to very small and practically immaterial 
deviations. 

But the theoretical consideration of dioptric questions establishes 
without doubt, that it would simplify greatly this problem, in which 
numerous conditions are to be fulfilled at the same time, if the optician 
had his choice of such glasses, in which the dispersion with the same 
index of refraction, or the index of refraction with a constant disper- 
sion, could be made to undergo a very considerable gradation. In 
this direction it must be looked upon as a progressive step, that the 
systematic use of a greater number of chemical elements in glass 
fusions makes it possible to create the varying grades referred to — 
that is, it enables one to extend the variety of glasses at disposal, in 
some places at least, in two dimensions, which heretofore had been 
essentially linear in character ; but the realization of this advance in 
practice may only be expected gradually, because of the necessity of 
supplying further theoretical and mathematical bases for these 
productions. 

The experiments led to the most satisfactory results, which, for 
the purpose of our catalogue, it would be unimportant to elaborate 
in further detail ; suffice it to say that the faithful endeavors of these 
men were universally appreciated, and that their conclusions gained 
the fullest confidence of those who were best able to judge of the 
value of their labors. 

The results were reached in the autumn of 1883, and the entire 
research would have been completed then, had it not been for the 



40 MODERN SURVEYING INSTRUMENTS. 

instigation on the part of several prominent scientists, that the investi- 
gators take hold of the practical application of their theoretical achieve- 
ments themselves, and to begin the industrial production of this article 
immediately in connection with the preceding laboratory research. 

This finally led to the erection of glass melting works at Jena, 
with all the facilities for successful practical operation, established 
with the cooperation of Doctors Carl and Rod. Zeiss, who had pre- 
viously given valuable assistance in the preliminary investigations. In 
the autumn of 1884 the factory was in condition to prepare for the 
production of optic glass on a large scale — both of the kind previously 
in use, as well as that of the newly created combinations. 

To carry out the necessary and very expensive experiments on 
a factory scale, it was fortunate that means were furnished by a num- 
ber of liberal appropriations granted from the Prussian State Treasury, 
which received the hearty endorsement of all scientific circles. 

After surmounting great and numerous difficulties, naturally 
retarding the progress in a new technical field, in which the enterprise 
is thrown entirely upon its own resources, without any assistance from 
previous experience, the Jena factory has now become a successful 
industry that has made its way to remain as a valuable permanent 
feature. Its capabilities have been sufficiently tested during the last 
eight years, in the intercourse with most of the optical works in 
Europe, so that it is now fully able to compete with them on a com- 
mercial basis. 

These remarks on the Jena glass factory will convince the reader 
that the article deserves that general preference which is universally 
given it — its evolution is one based upon a true scientific foundation — 
for, in this case, the practical application depended entirely upon a 
previous theoretical research, and theory and practice must work hand 
in hand to achieve lasting results. A new era in optics began when 
the Jena glass became a merchantable article. And this new optical 
advance was not without effect upon those fields of science in which 
optical apparatus is used, for the achievements in one particular line 
alone — in microscopy — received a fresh impulse from that time, which 
was again felt in other departments, as in physiology, biology, bacteri- 
ology, hygiene — those most important to the welfare of man. 

This short diversion leads us again to the subject of the telescope 
for engineering purposes, with which we are more particularlv 
concerned. 



THE A. LIETZ COMPANY. 41 

b. The Object Glass. 

Arrangements have been made by which our lenses are specially 
ground for us in Europe, and not one is accepted that will not stand 
the most critical test. We receive objectives and eye-pieces in sets at 
stated periods, so that we are always in position to supply our demand. 
Neither time, trouble nor expense has been spared to produce a tele- 
scope up to the standard of the most approved pattern, that shall 
possess all the refinement required of an instrument designed for 
scientific work. 

The objective is formed by a combination of two lenses, a crown 
and a flint glass, one of which is biconvex, the other plano-concave. 
The inner faces have the same curvature. As the concave lens has the 
longer focal length, this combination maintains the characteristics of 
one convex lens. The focal lengths are so proportioned that the disper- 
sion caused by the crown-glass lens is corrected by the flint — the well- 
known principle of counteracting the dispersion of light of one lens 
by interposing another of a different glass is made use of. 

Our objectives possess these achromatic lenses, made of the Jena 
glass, with special care, by the most skillful opticians. The focal 
lengths of these objectives vary from lyYi inches, in the case of the 
large Y-level, to 10 inches, in the large transit, and to y T / 2 inches in thp 
smaller instrument. 

In mounting the two lenses in the cell, great care is taken that 
their axes are made to coincide. Should this important point be neg- 
lected, an indistinctness of image would be likely to result. 

c. The Eye-Piece. 

The simplest form is the so-called Ramsden eye-piece, in which 
two plano-convex lenses are mounted so as to turn the convex surfaces 
toward each other. The distance between them is such that the chro- 
matic aberration of one lense is corrected by the other — which, how- 
ever, is not fully accomplished. 

Another form of eye-piece was invented by the optician Karl 
Kellner, of Wetzlar, and fully described in a paper published in 1849. 
It was called the orthoscopic ocular (from opOos straight, and (jkottco) 
observe), by reason of its principal advantageous feature of furnish- 
ing of every object a straight, perspectively correct, and, in every 
extent, sharp and well-defined image. The Kellner eye-piece also con- 
sists of two lenses : a biconvex collective, of which the flatter curvature 
is turned toward the objective, and an achromatic eye-glass, whose 
construction is similar to the Fraunhofer achromatic lens. According 



42 MODERN SURVEYING INSTRUMENTS. 

to the inventor's description, the three lenses used in this eye-piece 
possess only four reflecting - surfaces, and the two lenses composing 
the eye-glass must therefore come in absolute contact with each other. 
There may be two forms of the eye-lens : a plano-convex, with the 
curved face towards the collective ; and the double-convex. 

An ocular of this order, wherein both the collective and the eye- 
lens are compound, is the Steinheil eye-piece, which is doubly achro- 
matic, but which gives a very flat field. 

These forms of positive eye-pieces, wherein the focus of the 
objective lies in front of the combination, together with several of the 
negative form (the Huyghens and the Airy), wherein the objective's 
focus lies between the two lenses, give an inverted image, which is 
considered by many as an undesirable feature in surveying instruments. 
Nevertheless, they possess many valuable points in their favor, and for 
that reason they are universally adopted in Europe. In the first place 
this form admits of a greater amount of light than the erecting eye- 
piece. It also allows a longer focal length to the object glass, which 
is very important in correcting spherical aberration, besides 
increasing the magnifying power, which is a value dependent upon the 
ratio of the focal lengths of the object glass and eye-piece. 

We have always considered this inverting form the more advan- 
tageous of the two ; and we are convinced that if our engineers would 
accustom themselves to its use, it would finally be preferred. There 
is absolutely no difficulty in the inverted position of objects, and it is 
remarkable with how little effort the mind adjusts itself to it, so that 
the work may be done just as expeditiously as though the observer 
saw the objects erect. 

But, as the erecting eye-piece is in general demand, we do not 
intend to introduce the inverting one; all that we wish to point out is 
that the latter possesses many advantages not generally sufficiently con- 
sidered, and that seeing objects upside down is not an obstacle at all, 
for upside down and right side up are only relative impressions, which 
impose no task upon the brain. If the professors of civil engineering 
in our colleges would draw more attention to these facts, the results 
would soon be quite gratifying. 

The erecting or terrestrial eye-pieces require four lenses, placed 
so as to correct the chromatic aberration. In this form the inverted 
image of the object glass is again inverted, and an erect one is created 
between the third and fourth lens, which is viewed and magnified by 
the fourth. This is the form used for our transits and levels, and we 
can again insure our patrons that in this line nothing better is pro- 



THE A. LIETZ COMPANY. 43 

duced. The optical powers of the telescope are in perfect keeping with 
the accuracy of the centers, graduation and spirit levels, insuring a 
complete reliability and harmony in every part of the instrument for 
the most refined surveying work. 

The eye-piece (always erect unless specially ordered) is so arranged 
as to permit its easy removal, if necessary, by simply unscrewing it. 
In replacing, it should always be well tightened up. It is movable in 
and out by a revolving motion, turning the cap about- one-sixth of a 
revolution backward or forward — a manner which affords a finer and 
more precise focusing of the cross-wires than by means of a rack and 
pinion. 

Having reviewed generally the optical details of the telescope, we 
shall describe in a few words the mechanical construction of its other 
parts. 

d. Other Parts of Telescope. 

The slide, to which the object is attached, fits directly in the out- 
side or body of the tube. Particular attention is paid to this part to 
prevent even the slightest shake, and still procure an equal and sure 
motion, which is absolutely necessary, as no true adjustment of the 
line of collimation is possible otherwise. The motion is given by a 
spiral rack and pinion. 

The sliding tube is protected from dust and dirt by an exterior 
metal cylinder, called the slide protector. 

A sun shade is provided for the objective, which should always 
be attached, as the telescope, when focused to mean distance, is bal- 
anced with it; and a cap is provided for the protection of the objective 
when not in use. 

The cross-wire frame is suspended in the tube by four capstan- 
headed-screws, by which it is adjusted, the frame being so constructed 
that the cross-wires cannot be torn, in case the adjusting screws are 
tightened too much. 

The spider web used for our instruments is properly treated to 
avoid all twist, and to prevent its lengthening and becoming crooked 
in damp weather ; it cannot become loose, as it is well secured. 

For mining and tunnel transits we can provide proper means for 
illuminating the cross-wires — an arrangement that is readily supplied 
upon application. 

Quite a number of glass diaphragms have been cut by us for the 
United States Coast and Geodetic Survey. Instead of the spider webs, 
a small disc of very thin glass is fastened to the diaphragm, on which 
fine lines have been drawn with a diamond. It is readily seen that 



44 MODERN SURVEYING INSTRUMENTS. 

these cannot get out of shape, and for stadia measurements we think 
them of great advantage. The only drawback is that small particles 
of dust may settle on the glass disc, and, as they are in the focus of 
the eye-piece, they will be constantly visible to the observer. 

We make no extra charge for putting these diaphragms into our 
new instruments, if ordered in time. 

Stadia hairs are placed in our transits (and levels), when ordered. 
We have superior facilities for setting them with great precision to 
any desired ratio between distance and rod reading. It is customary 
to place them so that they shall read I foot on the rod for a distance 
of ioo feet, and to this measure we always have them in our stock 
on hand. 

The stadia hairs may be fixed or adjustable. We advise the fixed, 
as they are less liable to change their distance. In an adjustable set 
the observer is never certain that the position of the wires has remained 
unchanged. We have constructed a delicate optical and mechanical 
apparatus for fixing stadia hairs accurately to any proportion ; and 
by means of our powerful telescope, which has superior optical quali- 
ties, we can safely say that, with proper care and a little experience 
in that method of measuring, very satisfactory results may be obtained. 
The facilities for measuring across inaccessible places, and the speed 
with which it enables one to get distances, has brought this method into 
deserved prominence with our engineers. For topographical surveys 
it is indispensable. 

For the benefit of our patrons we have added a short treatise on 
stadia measurements, together with a table for correcting the observed 
reading to the horizontal distance and difference in level, which see 
under professional papers. 

When purchasing a new instrument, it is advisable to get one 
that has fixed stadia wires, which increases the cost only $3, while we 
charge $10 to put them into a transit or level sent to us subsequently. 

In sighting with the telescope it is of considerable advantage to 
have it reversible, and our transits are made so as to allow this free 
revolution in a vertical plane. The telescope balances accurately when 
in focus to mean distance, the friction in the bearings being shaded to 
such a degree of nicety that it shall neither work too hard nor too 
loose — a feature which ought to have very close attention. 

c. — General Remarks about Telescopes. 

When selecting or examining an instrument, the engineer should 
be particularly careful to test the qualities of the telescope. 



THE A. LIETZ COMPANY. 45 

It should have sufficient magnifying power to correspond with 
the finer qualities of the graduation, axis, centers, spirit levels, etc., of 
the instrument. There can be no doubt that the excellencies of each 
detail must compare with that of any other. 

Now, by using a low-power telescope, the defects of an inferior 
instrument may be hidden, or left undisc over able, and for this reason 
they will always be found in articles of lower grade. Had such an 
instrument lenses of sufficient magnifying power, the defects would 
become apparent to the engineer at once. We lay the greatest im- 
portance upon these facts, and for this reason call particular attention 
to them. Scrutinise the optical abilities of the telescope, and you will 
obtain the character of the whole instrument. 

For obvious reasons, some makers — but more especially dealers — 
give the magnifying power of the telescopes of their instruments much 
higher than it really is. An engineer should, therefore, be careful to 
convince himself of the real magnifying power before making a pur- 
chase. He will find it much to his interest to do so. 

We have found that the power of first-class instruments should 
be about twice as many diameters as the length of telescope expressed 
in inches. In inverting telescopes it may be materially increased, which 
shows again that they are of considerable importance in very high 
grade instruments. 

In another place we have added a practical method for finding the 
magnifying power of a telescope, to which we would advise our 
engineers to give some attention, and to make use of when about to 
choose an instrument. 

We have already pointed out the importance of perfectly center- 
ing the lenses, especially the objective. If this is not properly attended 
to, the adjustment can never be perfected for long and short distances. 

We have heard many complaints of various makes about the 
change in adjustment, and after careful examination we have found 
that the adjustments remained intact, but that the fault lay in the 
objective, which had not been correctly centered. We take great pains 
to center our object glasses perfectly, and to insert the lenses in such 
a manner that if taken out they may be replaced in the old position, 
which is secured by a notch and a pin. It is not advisable for engineers, 
however, to take these lenses from the cell, as their cleaning may be 
effected without removing them. 

Reverting again to the magnifying power of telescopes, it may 
be asserted that an increase thereof reduces the field. This is no defect, 
if the size of the latter is retained large enough to admit of stadia lines 



46 MODERN SURVEYING INSTRUMENTS. 

so placed as to read I :ioo. We often leave the field much larger, 
however, in which case there appears just a slight dimness at the ex- 
treme border; this is unimportant, for it does not retract any of the 
virtues of the glass, and possesses, if anything, an advantage of finding 
an object more readily. 

The quality of some of the telescopes of our best makers has 
often been questioned by competent engineers on account of a peculiar 
haze ascribed to the glass. This was found to be caused by a small 
film of moisture, which settles between the crown and the flint, and is 
not visible to the naked eye. We have been convinced, by advising 
with our optician, that the crown and flint glasses should always be 
connected with balsam. This does not decrease the amount of light, 
as formerly thought, but, on the contrary, it has advantages of clear- 
ness, in that it prevents foreign matter from settling between the lenses, 
which always destroys the image ; the refrangibility, too, is under more 
favorable conditions in the balsam. 

Extra Accessories for the Transit. 

There are a number of additions made for transits used for special 
purposes, and these we keep on hand, and supply them when called for. 

For laying off right-angles, for instance, we can make any pro- 
vision, if the customer will order it in time. In fact, any of the 
accessories, not usual in the ordinary complete field instrument, will 
be made as an extra if our patrons will notify us. 

For the solar attachment we provide a block with a thread on the 
telescope axis to receive the beautiful little apparatus known as the 
"Saegmuller Solar," of which a complete description will be found 
later. 

The Finish. 

This is made to give the instrument an elegant, tasteful appear- 
ance, without adopting a color glaring to the eye. Our instruments 
are finished in a number of hues, and may be bronzed to the special 
taste of the purchaser, if he chooses to order it. 

Size of Transit. 

The dimensions and proportions of the several parts of the transit 
are given in Part II of this catalogue, where the different sizes and 
varieties of instruments made are described more in detail. 

Packing. 

This is not at all an unimportant feature. Our transit is easily 
taken from the tripod by means of the Lietz friction coupling already 



THE A. LIETZ COMPANY. 47 

described, and set upon a wooden slide, to which it is fastened by means 
of two thumb screws and wooden clutches — a manipulation requiring 
but a moment's time. Nothing is taken from the instrument except the 
shade — it remains a complete whole from the base-plate to the top of 
the telescope. The board slides into the box with the transit in an 
upright position, with the clamps secured to keep it from turning. An 
extra place is provided for the solar attachment, if there be one. The 
door may then be locked, and the instrument is absolutely safe, with 
the least effort of packing and adjusting in the box. 

Rubber cushions are provided at the bottom of the case, to take 
up any sudden jar or jolt to which it may be exposed during transpor- 
tation. 

A rubber bag, or a silken one, may be had as an extra to each 
instrument, as well as a bottle of fine watch oil for lubrication of 
centers, etc., and camel-hair brushes for dusting. Likewise are a num- 
ber of adjusting pins supplied. 

The Tripod. 

We have adopted the new form of split leg — a construction which 
combines the greatest stiffness and strength with the least weight. The 
old form of the heavy solid leg has long since been abandoned, and we 
no longer make such a tripod, unless specially ordered by some con- 
servative customer, or for very small instruments. We aim to reduce 
the weight of everything, without sacrificing steadiness or strength in 
any particular, and that the split leg meets these conditions better than 
the solid one must stand to reason. 

The very best white ash is chosen and carefully worked. Instead 
of fitting the leg between two brass cheeks, we fit one cheek in the 
leg. In the older construction it frequently happened, in drawing the 
bolts closer to tighten a loose leg, that the cheeks would spring the 
plate, or weaken the screws that hold it. This is entirely obviated by 
the new arrangement of these parts, for the tightening can no longer 
affect the plate in the least. While in the former the leg would only 
fit at the lower part of the cheeks when drawn in by the bolt, it will 
always fit the whole surface of the cheek in the plan we follow, and 
after ten years' use it will be just as steady as when new. 

The shoes are made on a gradual taper to a sharp point, and 
securely fastened to the leg. They are provided with a projection for 
pressing upon with the foot when setting up. 

The large transit and the level fit the same tripod — in fact, any 
Lietz instrument may be readily fitted upon the tripod we manufacture, 
for the adjustment of the friction coupling allows a perfect accommo- 
dation to any slight variation in the parts of the base-plate. 



48 MODERN SURVEYING INSTRUMENTS. 

LEVELING INTRUMENTS. 

Lietz levels are manufactured in two different varieties, which 
we aim to keep constantly in stock, the Y -level and the dumpy level. 

In the manner of making these instruments, much that has been 
said of the transit will hold good here, and need not be repeated. 

The three main qualities to be secured in a level are : stability, a 
sensitive bubble and a powerful telescope. 

To secure the first, we need only refer to the solid construction 
of the star-shaped casting through which the leveling screws operate, 
already described in speaking of that feature in the transit. The Lietz 
coupling, too, plays an important part here, for we can make the tripod 
connection absolutely rigid. 

The center, or spindle, is almost three and one-half inches long, 
and is continued through the clamp up to the bar, which enables us 
to bring the center of gravity as near as possible to the tripod head. 
Great care is exercised in fitting the center to the socket, and, being 
made of the hardest composition, it must be apparent that it is an 
utter impossibility to wear out these parts, even by fifty years' constant 
use. The liability of bending the spindle, so common an accident with 
instruments having soft centers, and the fretting of the same, also 
likely to happen at times, is altogether avoided. 

The reasons for having a sensitive bubble have also been carefully 
set forth heretofore. Accurate work cannot be done with a sluggish 
bubble. No matter how much the virtues of the staying qualities may 
be extolled by some men, they are not fit for refined work if they do 
not answer the slightest touch of the leveling screw. If you can give 
a screw a twist or two before the bubble loses its peaceful equanimity, 
the work in hand would not be likely to inspire any great confidence. 

Our level tube* is curved, so as to give for every two minutes of 
arc a one-inch motion of the bubble. A refined level of this character, 
however, will only do good service in an instrument having perfect 
steadiness and a powerful and sharply defining telescope. If placed 
in a level so constructed as to be topheavy, or in one whose center is 
frequently exposed by being a part of the tripod head — and therefore 
liable to collect dust both on the cone and in the socket, introducing 
sources of error after every detachment — then it will indeed prove 
very annoying, should an active bubble accompany such an instrument. 
These structural defects are probably the cause why many of our 
engineers are prejudiced against sensitive levels, and prefer a sluggish 
or dull one. We can only assure the reader again that a lively bubble, 

* Also furnished reversible for extreme accuracy. 



THE A. LIETZ COMPANY. 49 

even if a little out of center by reversing the instrument, will still 
accomplish better results than an inactive one — one that gives the 
instrument an appearance of steadiness, which in reality it is far from 
possessing. An engineer only deceives himself if he trusts to a slowly 
acting level, which gives apparent satisfaction by concealing the errors 
that a sensitive one would soon indicate. A well-made instrument 
never suffers by having its qualities exposed by a high-grade bubble. 

The level telescope should have power and definition'. It is hardly 
necessary to make that statement, after all that has been .said on this 
subject in a previous chapter. It has been our earnest endeavor to 
obtain these results, without increasing the dimensions of the telescope 
and the other parts of the instrument, beyond the proper limits for 
steadiness and portability. A length of eighteen inches we have found 
to give the most advantageous results. Experience has shown us, that 
although an increased length adds to the magnifying power, it would 
only be of value if the other parts of the instrument were enlarged 
in proportion, which, on the other hand, would make it too heavy for 
convenience in carrying and offer more surface to the wind, thereby 
reducing steadiness, we believe that with our 1 8-inch level even the 
most extensive requirements in engineering are fully met. 

Our new and improved eye-piece, and the use of an objective of 
larger diameter than ordinarily found, enable us to obtain a magnifying 
power of 33. An increase of diameter adds very little to the weight 
of the telescope, and does not require a longer bar and larger plates, 
as an increase in length necessarily would, to retain steadiness. An 
aperture of i}i inches, used to its full value, affords a high illumina- 
tion with the above-mentioned power, as the tube is large enough to 
let all the rays proceeding from the object glass pass through to the 
field of view — an important point disregarded by a number of 
manufacturers. 

The diameter of the aperture of the object glass divided by the 
power, gives the diameter of the pencil of light entering the eye. In 
our telescope we obtain, therefore, i % -^ 33 = */ 24 of an inch, which 
shows that power and brightness are in accordance with optical law. 
To force the power beyond these limits we cannot conscientiously do, 
as that would be allowable only under certain circumstances — such as 
a perfectly clear atmosphere with a strong illumination of the object. 

The collars, upon which the telescope rests in the Ys, are made of 
the hardest bell metal, and admit of a position in either direction, that 
is, the telescope is reversible. The very first requisite is that these 
collars must be of exactly equal diameter and perfect cylinders. If this 



50 MODERN SURVEYING INSTRUMENTS. 

be not the case, the line of collimation will not be parallel to a tangent 
of the bubble's curve at its highest point, when the latter indicates a 
horizontal position, and, for this reason, a true level cannot be obtained 
with such an instrument. 

It is very often believed that in the course of adjusting the 
Y-level, by reversal of telescope and revolving on center, the bubble 
will indicate any inequality of the collars, but this is by no means true. 
If the Ys are both filed out to the same angle (this is generally the 
case, or at least very nearly so, as most makers file them out by means 
of gauges), the inequality of the collars may be quite appreciable, and 
yet the instrument will be adjustable in all its parts ; in other words, 
it may be so adjusted that the bubble on all reversals in the Ys and 
revolutions on center, will always give the same reading at both ends, 
that is, indicate a true horizontal position. A final test is necessary, 
therefore, after the instrument is properly adjusted, to ascertain the 
equality of the collars. This will be mentioned further on under the 
head of adjustments. 

Similar causes for error are introduced if a particle of sand lodges 
between the collar and Y, which illustrates the necessity of keeping 
these parts free from all dust and dirt. 

It is readily demonstrated to what considerable difference any 
slight inequality in the diameters of the collars may give rise to, but 
the space here will not permit of a mathematical discussion of the 
subject. 

We have carefully explained this defect, owing to the conviction 
on our part that it is a much more common one than is generally sus- 
pected. Numerous cases have come under our observation, where this 
fault existed in a remarkable degree. And in the perusal of many 
works on engineering and surveying, we have noticed very few that 
call attention to this material defect, and still less that give a correct 
test for it. 

We are aware that accurate leveling may be done with a level out 
of adjustment, if the utmost precaution is taken to have equi-distant 
fore- and backsight. But looking at it from this point of view, why 
not use the dumpy level then, instead of the more costly Y-level ? 

The Finish is made to give the instrument an elegant appearance, 
and yet obtain all the qualities alluded to in a previous discussion of the 
same subject. The telescope is usually cloth finished to avoid that 
unequal expansion of the metal heretofore mentioned. This finish is 
of a color pleasing to the eye, is applied so that it remains intact for 
a long time, and if somewhat worn after a long period of exposure, it 



THE A. LIETZ COMPANY. 5 1 

can be readily reapplied without difficulty at a trifling expenditure. The 
cloth finish is a modern feature, and one that is so universally pre- 
ferred, that we have no hesitation in recommending it to our patrons 
as worthy of their consideration. However, we keep in stock the 
bronzed and lacquered, as well as the cloth-finished level telescopes, so 
that the customer may have his choice in the matter. 

The level telescope is supplied with a slide protector and with a 
sunshade; the latter should always be put on to balance it evenly. A 
cap is also provided for the objective and a shutter for the eye-lens. 

In all other matters the transit details obtain here also. 

Fixed stadia wires are supplied, set to read I :ioo, for which an 
extra charge is made if ordered. 

The center movement is checked and regulated by a clamp and 
tangent screw, exactly similar to those of the transit. 

Other useful accessories are attached, but any feature not usually 
found in the Y-level, must be ordered beforehand. If desired, we place 
agate fittings in the Ys for the collar contact, but for this we also make 
an extra charge. 

We are likewise in a position to make, but upon order only, levels 
of precision for the most exact work that the geodetic surveyor is 
called upon to perform. These are provided with all the delicate 
details that such an instrument must possess. We invite correspond- 
ence upon the subject of geodetic instruments, and will cheerfully 
furnish prices after consulting with our patron upon the nature and 
character of the instrument required. 

The packing in the case has been made so as to assure safety in 
transportation, with the least trouble and inconvenience to the operator. 
The level is taken from the tripod by a third of a revolution of the 
base plate, which undoes the Lietz Coupling. It is let down to stand 
upright in the box, when the closing of the lid holds everything firmly 
in place. In all minor details the level box is similar to the transit 
case, every means being employed to insure absolute safety. 

The Dumpy Level. 

In this instrument the aim has been to construct it in such a 
manner that it shall be as compact as possible by dispensing with 
certain features of the Y-level, not absolutely necessary in order to do 
good and reliable work. 

The principles governing its construction are the same as those 
that obtain in the more elaborate Y-instrument. 

The telescope is permanently held by two vertical arms attached 



52 MODERN SURVEYING INSTRUMENTS. 

to the level bar, and cannot be taken therefrom. The level tube rests 
upon these arms, over the telescope, and is also fixed. The telescope 
tube is thereby brought as close as possible to the tripod head, which 
is a desirable characteristic. All the other features remain the same 
as in the Y-level construction. 

This instrument, which is almost exclusively used in Europe, has 
not yet met with that favor by American engineers, which its simplicity 
and accuracy so justly deserves. This is due partly to its greater 
inconvenience in adjusting as compared with the Y-level, and partly 
on account of defective construction, inferior telescope and other 
neglected details, which usually obtain in instruments of this kind. 

We are confident that a dumpy level possessing a good telescope, 
sensitive bubble and stability, will do just as good work as the more 
costly Y-level. While the adjustment of the latter is made more 
readily, the former will retain it longer. 

Our dumpy level has a bronze center, a 15-inch telescope, and a 
vial of such curvature, as to give for each inch of motion of the bubble 
an angle of three minutes. 

There is no clamp or tangent screw to this form unless ordered 
by the customer. 

The bar, telescope and vial case are. cloth finished, and the latter 
may be provided with a folding mirror, which acts as an important 
protection to the more exposed spirit level when shut down, or as 
an indicator to the observer at the eye-piece, of the exact position of 
the bubble, when elevated. 

The stadia hairs may also be supplied to the dumpy level. 

Other Levels on Sale. 

In addition to the high grade instruments described, we also keep 
on hand a supply of smaller and less costly goods for leveling. With 
these instruments work may be done by the ditcher, irrigator, con- 
tractor, grader, farmer, dike-builder, gardener, plumber, architect, 
forester and military man, sufficiently precise for many ordinary pur- 
poses, wherein great accuracy is not required. 

For a more detailed description of these instruments, see Part II 
of this catalogue, containing a price list of articles on sale. 

Remarks. 

In the foregoing we have endeavored to give the reader a fair 
idea of the principal engineering instruments made by this firm. We 
desire to convince our future customers — our old patrons we have long 



THE A. LIETZ COMPANY. 53 

since convinced — that we are building conscientiously upon scientific 
principles, that every part and detail has been carefully studied to 
meet the requirements of our engineering fraternity, of the climate, 
and of all those conditions that influence the shape and character of 
every feature of the surveying instrument. It must permit of all 
operations at the least expenditure of time, it must be compact, it 
must be light, it must be absolutely accurate, it must be rigid, it must 
be stable and it must possess strength. And wherever a possible im- 
provement is suggested in any detail, it must be applied at once and 
tested as to its probable merits, and if it prove of value, no time must 
be lost in introducing it. These are the principles that have governed 
the manufacture of the articles which we have brought to your notice. 

New improvements have always had our attention, without any 
regard of the expenses incurred in experimenting. We need only 
refer to the introduction of aluminum in the manufacture of survey- 
ing instruments, which, we are fully convinced, has been crowned with 
success, to prove to our patrons that we never allow any conservative 
notion to rule the establishment. The particulars of this new field of 
manufacture will be found in another chapter of this part of the 
Manual. 

With the object constantly in view to make only the very best 
article that can be procured anywhere, and ever ready to introduce 
improvements and to experiment with suggestions that may lead to 
them, our instruments are held at a price that is commensurate with 
their qualities. Their values are rated by those current among first- 
class instrument makers ; they are no more, but they are no less. We 
do not handle cheap goods, and the trade that we are most anxious 
to please is that willing to pay a fair price for a number-one article. 

It was our purpose to describe in this catalogue only the instru- 
ments for which there exists the greatest demand, and for this reason 
we do not intend, at this time, to enter into any detail of the manu- 
facture of other scientific apparatus that we are in position to furnish 
upon due notice. 

Theodolites of the highest grade for the most exact purpose, 
reading with micrometers to the most refined division, will be made 
upon order to any desired shape and design, and with every required 
accessory. 

We also manufacture the topographer's plane-table , either in its 
simplest form, as recently perfected by the highest authorities, or in 
its most delicate arrangement of parts, as devised for work of the 
greatest precision capable of being put on paper. A number of plane- 



54 MODERN SURVEYING INSTRUMENTS. 

tables made for our institutions of learning, and for surveying depart- 
ments of the U. S. Government, have given absolute satisfaction, as. 
shown by testimonials in our possession. 

The modern improved plane-table alidade is a particular specialty, 
to which we have given considerable time and attention. This instru- 
ment has been constructed by us of aluminum, which has been a per- 
fect success, proven by the fact that one of them has been almost daily 
in use for many years, under very trying conditions, without giving 
rise to the first complaint. Under the head of Aluminum for Sur- 
veying Instruments, this will be again referred to. By a combination 
of aluminum and aluminum bronze, the center of gravity of the 
alidade may be brought close to the foot of the standard, which is a 
very essential point in its construction. 



ALUMINUM FOR SURVEYING INSTRUMENTS. 

A great deal has been said and written about this comparatively 
new metal of late, so that its characteristics have become generally 
known. 

Its color is a dull white, similar to silver, and rather pleasing to the 
eye. It embodies many qualities that make it a very valuable material 
in the mechanic arts. It is quite soft, but possesses malleability, 
tenacity and ductility, so that it may be made into very thin sheets, 
or drawn out into fine wire. It is a conductor of heat and electricity. 
One of its principal features is that it does not oxydize in the atmos- 
phere, and that it does not lose its brightness under conditions that 
would tarnish silver and blacken it, for sulphuretted hydrogen or sul- 
phide of ammonium do not influence its color. But the greatest ad- 
vantage is its remarkable light weight, the specific gravity being only 
2.6, or one-fourth of that of silver, and for this particular quality its 
use has been sought in the manufacture of articles requiring small 
weight, ever since the cost of its production has justified it. 

One of the many alloys is the so-called aluminum bronze, which 
unites hardness with malleability, and is therefore extensively used 
for many purposes. This alloy, however, gains little in lightness 
as compared with the ordinary metals. 

Since it has been the constant aim to produce field instruments 
that shall combine strength with the least practical weight, there could 
not have been found a better application for aluminum than in the 
instrument-maker's art. 

It was necessary to experiment with it in different directions, 



THE A. LIETZ COMPANY. 55 

particularly as to the proper alloy — it being much too soft in its pure 
state — that shall give the required tensile strength and stiffness, make 
it workable without fretting, and yet add little to its weigh. An alloy 
with silver is now made that fully satisfies these conditions. 

One of the principal objections urged against it in the manufacture 
of surveying instruments is, that on account of extreme lightness they 
would not be steady enough in the wind. This firm has built over 
iooo transits and levels of aluminum, and, in our opinion, they are 
quite as rigid as any other, if properly constructed, care being taken 
to adhere to the old material in such details where it cannot be dis- 
pensed with.* We have found that the stability of an instrument 
depends more particularly upon the construction of its lower parts. 
If the combination of base-plate and leveling apparatus be made so 
that the instrument can be rigidly held, the center of gravity may be 
brought down lower, and that in itself would tend to increase its 
stability. 

Aluminum transits are made by the A. Lietz Company in three 
sizes, being complete field instruments with every accessory. The 
large transit weighs 7^2 pounds, and the smaller one 3 pounds, which 
reduces the weight about one-half. The construction is precisely the 
same as in the instruments already described. 

The base-plate is of composition metal, the inner center of the 
hardest bell metal, and the outer center of bronze. The leveling screws 
are also of composition, as well as the telescope axis. 

These transits may either be left in the beautiful natural color of 
the metal, or other shades may be applied. The standards are cloth- 
finished. 

The Saegmiiller Solar Attachment is now made of aluminum, 
which can only be an improvement in any direction, whether its weight 
be added to the top of a transit made of the red metal, or to one of 
the new metal. Lightness in the solar attachment is a very desirable 
feature, and that may be easily obtained now. 

In the Y -level the base-plate and leveling screws and center are 
of composition metal ; the collars, the hardest bell metal ; and the rest, 
aluminum. It has an 18-inch telescope, its weight being 5^ pounds. 

We also manufacture a plane-table alidade of aluminum, with a 
ruler of aluminum bronze. This instrument, although of the same 
weight as one of the ordinary metal of the same size, possesses the 
particular advantage of having its center of gravity as low as it can 
possibly be brought to the table, and that when placed upon the board 

* See Testimonials for instruments made of our aluminum alloy, on fly-leaves. 



56 MODERN SURVEYING INSTRUMENTS. 

it will be absolutely stable, and will not be influenced by the wind, 
which causes the ordinary alidade to tremble and travel on the paper. 

And this is the reason why we should object very strongly to an 
aluminum rule in a plane-table alidade. This part of the alidade 
should be of heavy material, as well as the lower part of the standard, 
while the rest may be constructed as lightly as possible. In this case 
little or nothing may be gained in the weight, but very much is gained 
in stability, when compared with an instrument made of one metal 
throughout. Under no condition should the rule, which is the base 
of the structure, be made of a light material. 

After fifteen years of experience in the construction of aluminum 
surveying instruments, we are ready to advocate the judicious use of 
this material. We have applied it in transits and levels, and have 
accomplished a saving in weight of about 50 per cent. Great care is 
exercised in the proper distribution of the metal. We have already 
stated that in a transit aluminum is never used in the construction of 
the base-plate, centers, leveling screws, telescope axes and all minor 
parts having threads. The principal horizontal members, the plates > 
are of aluminum, strongly ribbed. 

Much has been written about its high coefficient of expansion,, 
and particular stress has been laid upon the effect of unequal expansion 
necessarily induced by the use of different metals. If this matter be 
considered for one moment, however, it will soon be seen that practi- 
cally there can be no serious result from this source. In the first 
place, the difference between the coefficients of brass and aluminum 
is altogether too small* that the effect of any possible distortion in 
material judiciously placed need necessarily be feared. Glass plays 
a very important part in the make-up of a transit. The coefficient of 
expansion in glass is very low (0.8 mm. per meter, raised ioo° C) 
and a metal best adapted for our purpose would be one having the 
same coefficient. Now, as far as brass and aluminum are concerned,, 
it is readily seen that there is practically no difference in them when 
compared with glass. As long as glass is used, one may as well 
employ aluminum as brass for the constructive parts, for while the 
expansion of the latter exceeds that of glass 0.000072 inches per linear 
foot for i° Fahrenheit, that of the former does so only by 0.000103. 
Unequal expansion, therefore, is not a source of error that need 
reasonably be feared. 

The more vital objection to a light instrument — its greater un- 



* (The Physical Laboratory of the German Empire has established the following: For 
brass 1.88 mm. per meter of length, raised in temperature ioo° C; for aluminum 2.34.. 
Our reductions are made from these data.) 



THE A. LIETZ COMPANY. 57 

steadiness in the wind when compared with a heavier make — is some- 
thing we have already referred to. We have made and sold over iooo 
aluminum transits and levels, and every one has been a proof of our 
statement made fifteen years ago : that the stability depends more 
upon the construction of its base and connection with the tripod than 
it does upon the weight of what may be called its superstructure — 
the part above the leveling head. 

It may also be mentioned incidentally that a fall will injure an 
aluminum instrument less than if made of red metal. Not only is this 
theoretically correct, but our actual experience in this line has proven 
to us the fact that from ordinary accidents the lighter instruments 
are always less seriously injured than the heavier ones. 

The testimonials from our customers will show the public that the 
aluminum instruments made by our firm have given the fullest satis- 
faction, and have not disappointed our expectations. 

We are firmly convinced of the adaptability of aluminum for sur- 
veying instruments, and for that reason our firm has gone extensively 
into that branch of manufacture, for which every facility has been 
added recently to the capacities of the shop. The aluminum instru- 
ment is fifty per cent, lighter than the other, is just as strong, is just 
as precise in its workings, possesses every requisite detail of a com- 
plete field instrument, and, we claim, is just as stable. Those of the 
engineering fraternity who have to carry the transit all day, the mining 
and railway men, who climb the mountain sides during the long sum- 
mer days from early until dark, will not be long in finding out these 
advantages and in putting them to a severe test in every direction. 
After manufacturing aluminum instruments for fifteen years we have 
had no occasion to regret it, and find constant encouragement from 
the best professional men. 



CARE OF INSTRUMENTS. 

The greatest source of danger to a delicate instrument is careless 
handling. It is often subjected to violent usages for which there is 
absolutely no need. The rude way of manipulating its delicate parts ; 
the unnecessary display of digital strength in operating a clamp; the 
useless strain applied to the leveling screws; the careless manner of 
carrying it ; the rough method of taking it out of its case, or replacing 
it ; and the incautious closing of a lid or door of a box by force, before 
the instrument is somewhat adjusted to its position; all these are 
sources of danger that vitiate its adjustments and cause no end of 



58 MODERN SURVEYING INSTRUMENTS. 

trouble and expense. Although a well-made instrument is so designed 
as to stand many a shock without direct injury, any daily repeated 
abuse is sure to have its ill effect, from which your work must suffer. 

As the usefulness of a transit or level may be preserved for many 
years by a little attention to details, we shall enumerate a few of the 
principal points which the engineer will do well to observe. 

Always protect your instrument from rain by throwing over it 
a waterproof bag; and if it gets wet at all, clean it thoroughly after 
getting under shelter. It is not well to enter a hot room from the 
cold air, without giving it some protection. The condensing vapor 
settling on the metal and glasses is certain to give rise to injuries. 
It is always safe to place the instrument in its case before going into 
a warm room in winter. It is not wise to leave your transit or level 
exposed for hours to the hot sun. Shade must be given either by a 
hood thrown over the instrument, or by holding an umbrella. 

But accidents are liable to happen, and for that reason we have 
noted down a few remedies in case of an emergency. 

The general tendency in the use of the screws is to overstrain 
them. This should never be done, especially with the cross-wire 
screws, which, when brought up too tight, are liable to constant change 
and loss of adjustment. The leveling and clamp screws, if over- 
strained, wear out sooner and may show fretting. If this takes place, 
they should be taken out and brushed with a little coal oil or benzine. 
The nuts are best cleaned by screwing a flat piece of soft wood through 
their apertures. In putting them together oil them slightly. 

Fretting of the centers and of the telescope-slide will interfere 
more with a correct working of the instrument than any other part out 
of order. They should be watched, therefore, very closely, and as soon 
as any rough motion manifests itself, it should be remedied at once, 
if possible, by an instrument maker. If this cannot be had, and the 
fretting is in the slide, first scrape and then burnish down the place 
where it frets. It may also be ground slightly with oil and very fine 
pumice stone dust, which is best obtained by rubbing two pieces on 
each other. After grinding then a little, the tubes should be cleaned 
and placed together again with oil only; then move them in and out 
a number of times, wipe the oil off, and finally put them together 
when dry. Should the fretting occur in the centers (if properly made 
and constructed, so that they do not come apart in detaching the 
instrument from the tripod, this will never happen), employ the same 
means ; and if this be not effective, place a washer, made of paper or 
a thin card, between the shoulders. This will cause a shake, making 



THE A. LIETZ COMPANY. 59 

accuracy impossible, and will introduce errors of parallax in reading 
off, which is better, however, than to destroy the centers wholly. The 
best unguent for them is very fine watch oil. Regarding our centers, 
we are fully prepared to assure our customers that no fretting will 
ever happen, as they are never exposed, and made with the utmost 
care. 

The object-slide should not be oiled. Never, under any condition, 
use emery in trying to repair an instrument, as it cannot be removed 
again and will grind continually. 

An efficient lubricant for leveling screws, clamps, pinions, etc., is 
well-rendered marrow. 

If an instrument is upset, thereby bending centers and plates, 
do not turn it unnecessarily, as this will disfigure the graduation, but 
send it to a competent instrument maker immediately. There should 
be no delay in repairing defects. 

In the matter of the tripod, it is wise to look to the screws that 
hold the legs frequently, and to keep them well tightened up; and to 
inspect the shoes, to see that they do not come loose. An instrument 
cannot be steady if there is any shake in the tripod, which is its sup- 
port and must be firm in every particular. 

The graduation is a very delicate detail to handle, and should be 
approached only with the utmost care. It is safe to leave this part 
to the instrument maker, and not to attempt to remove the plates, as 
they cannot be properly recentered without the aid of a testing 
apparatus. An exposed graduation may be cleaned with a little watch 
oil and a chamois skin, taking care not to touch the edges while this 
is done. 

To preserve the sensitiveness of the needle, the center pin must 
be prevented from becoming dull. The instrument should never be 
lifted without raising and arresting the needle, and if, upon letting 
it down again, the swing is too large, gently stop it when within a 
few degrees of its natural bearing. Every check and start must be 
made gently, never abruptly. Should the point become dull, it is best 
to send it to an instrument maker; if this be not practicable, a watch- 
maker may perhaps attend to it. It should be remembered, however, 
that the point of poise must be centered — that is, occupy the center of 
the graduated circle. This cannot be done by a watchmaker, and is 
only to be relied upon if made in an instrument maker's shop. 

If a needle is made of good steel, well hardened and properly 
charged, it will not often lose its magnetism ; and if, when placed 
away, it is always brought to line in the meridian, it will retain, or 



60 MODERN SURVEYING INSTRUMENTS. 

even increase is polarity. If a needle has lost its magnetism it may 
be charged again with an ordinary horseshoe magnet; one of three 
inches in length will be suitable for this purpose. The operation is 
this : hold the magnet with the poles upward, then, with a gentle pres- 
sure, pass each pole of the needle from center to extremity over the 
opposite pole of the magnet, describing before each pass a circle with 
a diameter of about double the length of the needle, taking care not 
to return it in a path near the pole. If the magnet is strong enough, 
the needle need not be taken out at all, but by raising it against the 
glass and then passing the magnet over this, it will be charged suffi- 
ciently. After charging, the needle has lost its balance, which may 
be easily restored by shifting the balance wire on the south end. 

The observer should always satisfy himself that there be nothing 
about his clothing, especially in the make of the buttons, that would 
have any influence upon the needle. 

In the matter of the telescope, intelligent handling will do much 
towards preserving its accuracy and reliability for a long time. In 
cleaning any of the lenses, use a soft rag or chamois leather. If the 
glasses should become greasy, or very dirty, wash them with alcohol. 
The inner faces will seldom require cleaning, and it is not advisable 
to take the telescope apart too often, as it is likely to destroy 
its adjustment. If dust should settle on the cross-hairs, it is safest 
not to touch them. The only remedy that may be tried is to take out 
both the object-glass and<the eye-piece, and to blow gently through the 
tube. This may remove the dust without injuring the threads, but it is 
quite a delicate operation. 

Cross-hairs may be replaced in the field by the engineer. The 
spider web is cleansed from dirt by placing it in water for a few 
minutes. A little manipulation readily removes any particle that may 
adhere to the thread. After drying for a moment, adjust it to the 
diaphragm, previously cleaned from dust, and attach it by means of 
a little shellac. It requires considerable practice to do this nicely, 
for a spider's web, although quite strong, cannot be handled by clumsy 
fingers without parting; but in the case of an emergency the engineer 
must try to do the best under all circumstances. 

Referring again to the lenses, it is well to remember that in taking 
them apart, the centering is disturbed, and the engineer is not able to 
replace them properly, especially if they fit loosely in the cell, which 
is very often the case. The staining of flint-glass lenses is caused by 
the corrosion of the oxide of lead contained in the glass. This will 
generally occur when the lens is kept in a damp place for some time. 



THE A. LIETZ COMPANY. 6l 

In cleaning* an object-glass, care should be taken not to rub it any 
more than necessary. Brush off the dust first with a camel-hail brush, 
and then wipe it carefully with a clean piece of chamois leather. If 
very dirty, wash it with alcohol or water and soft chalk, being careful 
to have the latter free from grit. 

Considering that, in cleaning, each rub will destroy more or less 
of the fine finish of the lens, upon which depends the brightness and 
brilliancy of the image, the surveyor will be well repaid for his care 
in this particular. 

Similar attention must be bestowed upon the eye-piece. With our 
high power eye-pieces, a motion of only three-sixteenths of an inch is 
necessary to allow for difference in eyes. As the sliding motion is for 
this purpose alone, it is not at all necessary to disturb it after it has 
once been properly adjusted, as long as the same person is using the 
instrument ; even in packing it away in the case the eye-piece may be 
left so, as this extra extension is allowed for in the box. The cap is 
provided wih a slide to protect the eye-lens from dust while the instru- 
ment is not in use ; the engineer should never neglect to close this, and 
to cover the object-glass with its cap as well, as soon as the instrument 
is set at rest. 

Repairs.* 

We are fully prepared to make careful repairs to all instruments, 
from the graduation of an arc or circle, and the straightening of a 
center or plate, to the setting of a simple screw. In this particular 
branch we have operated here for the last twenty-six years, and have 
gained the fullest confidence of our people. We need only state here 
that we guarantee satisfaction to our customers in every way. 

As we are located in California, separated by the breadth of the 
continent from our Eastern colleagues, we are necessarily required to 
repair instruments of almost every known make, and this has com- 
pelled us to procure the various requisites in the workshop for all 
emergencies. Today we are in the position to renew any part of an 
instrument, no matter where it was originally manufactured. Time and 
money will be saved by sending directly to us, and we shall try to give 
our customers every satisfaction. Whatever is entrusted to us will 
be thoroughly overhauled and put in the best possible condition, unless 
specified orders are received to confine the repairs to certain details. 

* Experience has taught us that it is not wise to allow an ordinary mechanic to attempt 
instrumental repairs, as frequently resorted to in inland towns. It is always the case that 
this proves ruinous to the instrument, and subsequent repairs will be more extensive and 
expensive than if it had been shipped to the instrument-maker at once. Express charges 
are of far less importance, and may be made very reasonable. See notice in front of 
this manual. 



62 MODERN SURVEYING INSTRUMENTS. 

As a general thing it ought to be left to our judgment as to what the 
instrument requires ; it may cost a little more if you follow our advice 
in this particular, but it will certainly be more satisfactory in the end. 
It will save time, trouble and additional expense. In the course of our 
examination of an instrument needing repairs, we discover defects that 
could not be apparent to any one before its parts were separated and 
individually tested. What may appear of no consequence, and is there- 
fore neglected, is quite likely to lead to all sorts of subsequent inaccu- 
racies in your work. Years of experience in this particular line have 
taught us the advisability of urging this point upon our patrons. 

Considerable correspondence is had from inquiries about the cost 
of repairs. Although it is impossible to state the exact figures before 
an examination, there are certain rates for ordinary repairing that we 
may mention here. 

The most expensive instrument in this regard is the transit, being 
the most complicated in parts. If injured by a fall, new centers and 
a new telescope axis are generally required, the cost varying from $10 
to $30, reaching sometimes as high as $50. If slightly injured it will 
vary from $5 to $10. 

Injuries sustained by leveling instruments are generally less 
serious.* A new level vial costs from $2 to $7.50, according to size 
and sensitiveness. Instruments defective in construction or workman- 
ship will not require a sensitive level, as that would be a source of 
constant annoyance to the engineer; the bubble should be chosen to 
harmonize with the general qualities. As a rule, we attach to the 
better class of instrument a level that shall give for each inch of motion 
of the bubble an angle of two minutes ; to the inferior grade, one of 
three or four minutes. 

Compasses sent to us are generally injured by the dulling of the 
center pin. Sometimes the plates and sights are bent and the glass 
broken. Often the center cap is worn out, and a new one is required. 
The cost of repairing ranges from $2 to $8, and even as high as $10. 
A new needle, having the largest breadth in a vertical direction, which 
is far superior to the flat style, costs $5. A new center pin, 75 cents. 
New center cap with jewel, $1.50. 

Careful readjustments made under the collimators are charged 
for at the rate of $2.50 for each instrument. 

Transits and levels should always be accompanied by the leveling 
plates ; the tripod and head need not be sent. With compasses the 
ball spindle should be sent. 

We advise our customers to pack their instruments carefully, when 



THE A. LIETZ COMPANY. 63 

sending them to us for repairs, as they are liable to material injury 
if this precaution be neglected. The space in the box between the 
different parts — of the transit particularly — may be filled with soft 
paper wads to protect it from jars and blows. It is well to put the 
case in an additional box, a little larger in dimensions, in such a man- 
ner that the top of the case is plainly visible and its leather strap handy 
for carrying. The space between the case and the box may be padded 
with shavings, or some soft material to take up the shocks. Mark upon 
the top of the box in large legible letters : 



This Side Up ! ! 
Scientific Instrument 
Handle With Care ! ! 



And ship through a responsible express company, plainly addressed to : 

THE A. LIETZ CO., 

632-34 Commercial Street, 

San Francisco, Cal. 

The name of the sender and his address, together with the value of the 
instrument, should also appear on the box. 

This will insure comparative safety in transportation, which is a 
point that should be well observed by the engineer. And this precau- 
tion would also increase the responsibiliy of the carrier, in case the 
instrument had suffered during transportation. 

When an instrument is sent to us for repairs, a letter or postal 
card should be mailed at the same time, to inform us of the fact, 
giving the necessary directions, and stating when the return is required. 
The receipt of the instrument will be acknowledged by us at once. 

ADJUSTMENTS. 

Adjusting an instrument consists in delicately moving to the right 
or left, and up or down, certain parts that must be either parallel or 
at right-angles to each other. This is done by slightly turning a num- 
ber of capstan-headed screws or nuts by means of a small steel rod, 
called an adjusting pin. Adjusting the vernier and compass consists 
in placing certain points in a straight line ; but as these corrections are 



64 MODERN SURVEYING INSTRUMENTS. 

always made by the instrument maker, they do not properly apply to 
the subject before us. Verniers, limb and needle, if properly placed 
at the outstart, will not need any correction in the ordinary use. 



Of the Transit. 

i. Adjustment for Parallax. — This is a very essential one, 
and must be looked to carefully in every surveying instrument, whether 
transit, level or theodolite. It consists in so focusing the eye-piece 
that the cross-hairs shall stand out distinctly and well-defined, when 
the telescope is directed upon an object in focus. If this is not properly 
done the hairs will be dim; they will appear to travel and to seem 
unsteady when set on a mark. We know that this has given consid- 
erable vexation to the observer, and instruments have been disparag- 
ingly condemned for their apparent parallax, when nothing more was 
necessary than a slight movement of the eye-tube to focus the hairs 
properly. This fact should be well borne in mind. Our eye-pieces are 
quite easily moved in or out by a revolving motion, which affords a 
very fine and precise adjustment to focus. 

Operation. — Direct the telescope so as to have a clear view of the 
sky, and then turn the eye-tube by the cap as just described, until the 
cross-hairs stand out like two sharp and distinctly drawn black lines. 
After a few trials this is accomplished without difficulty. Then try 
the telescope upon some object brought into focus and test the clear- 
ness of the wires. A point now bisected must stay so while the eye 
is moved laterally in front of the eye-hole. If it remains stationary, 
there is no parallax and the adjustment is made. Once properly set, 
the eye-piece may remain for the same observer for all time, and need 
not be adjusted from day to day. Attention has already been called 
to this point in a previous chapter, where it was noted that the instru- 
ment box was made large enough to allow the eye-piece to extend 
beyond the tube. (The sun-shade should be put on the telescope first, 
and then focused to mean distance to balance it properly.) 

2. Plate Levels. — The object is to set the levels at right-angles 
to the vertical axis of the instrument, so that when the bubbles are 
centered the axis is truly vertical. 

Operation. — Bring the bubbles to the middle of the tube by means 
of the leveling screws, then turn the instrument on its center 180 
degrees. If they remain central for any position, they are in adjust- 
ment ; if not, they must be elevated or depressed at one end to correct 



THE A. LIETZ COMPANY. 65 

them. One-half of the required correction is made with the capstan- 
headed screws on the vial case, the rest by the leveling screws of the 
instrument. Several repetitions of the operation may be required be- 
fore attaining accuracy. It is well to have the plate in such a position, 
that the levels shall be parallel to a pair of opposing foot screws. If 
they are out considerably, it is better to adjust one first, approxi- 
mately, and then the other. 

3. The Standard Bearings. — The telescope should revolve in 
a vertical plane when the instrument is level. One end of the tele- 
scope axis must be either raised or lowered until accuracy is reached. 
A capstan-headed screw is attached for that purpose. 

Operation. — Set the instrument up within about fifty feet of the 
wall of a house. Take a well-defined point as high up as possible on 
he wall ; clamp and bisect ; then turn down the telescope and put a point 
in line as low on the wall as may be conveniently reached. Reverse 
the telescope and direct again to the upper mark, if you please ; clamp 
and bisect ; turn down to the lower mark, and if it is bisected, the 
telescope revolves in a vertical plane and requires no adjustment. If 
it does not strike the point absolutely, one-half of the difference is 
taken up by the capstan-headed screw, and the adjustment is done. 
Several repetitions of the operation may be required. It is not neces- 
sary to level the instrument, but it should be brought in such a position 
as to admit the bisecting of two well-defined points. Care should be 
taken, however, that the observation is made at the intersection of the 
cross-wires, and that the instrument is securely clamped. 

This adjustment should always be made before that of the cross- 
wires, for this reason : that unless points of equal height are taken 
in the subsequent adjustment of the vertical hair, it will only then prove 
correct, if the telescope revolves in a truly vertical plane. It is, there- 
fore, always better to look to this before the cross-hairs are adjusted. 

This adjustment may also be made by means of an accurate strid- 
ing level, such as manufactured by this Company for use in high-grade 
instruments. The transit must be precisely leveled up by the foot- 
screws and plate bubbles, after which the striding level is placed across 
the telescope, resting upon its axis. It is evident that the bubble will 
indicate any deficiency in the horizontal parallelism of this axis, and, 
therefore, any error in the true vertical motion of the telescope, which 
may be corrected until the bubble of the striding level remains centered. 

4. The Cross-wires. — The line of collimation should be at right- 
angles to the axis upon which the telescope revolves. 



66 MODERN SURVEYING INSTRUMENTS. 

Assuming that all the required conditions have been fulfilled by 
the instrument maker — having placed the telescope in the center of the 
instrument, and having the tubes perfectly straight and normal to the 
telescope axis, which are necessary instrumental requirements, there 
are two methods that may be employed. One is by means of back and 
fore-sights, which is that generally used; the other consists of a test, 
by means of three points in a range, where the middle one is occupied. 
Preceding either method the hair should be made truly vertical, so- 
that either the upper or lower end will bisect a point when the tele- 
scope is moved up and down. This is easily done by loosening the 
diaphragm and turning it slightly in the required direction. To accom- 
plish this the instrument must be leveled up. 

Operation, First Method. — Occupying a point, direct the telescope 
to some well-defined mark, about four hundred or five hundred feet 
distant ; clamp and bisect it ; then revolve the telescope and place a 
point in the opposite direction at about the same distance. Now un- 
clamp and turn the instrument half-way around ; set the hair again on: 
the first point, revolve the telescope and sight to the second point. 
If the intersection bisects the latter, the vertical hair is in adjustment. 
If not, the error can be corrected by the capstan-headed screws, which 
afford a lateral motion of the diaphragm. With them the vertical 
thread should be moved one-fourth of the space intercepted between 
the direction of the telescope and the direction of the second point. 
Several repetitions may be necessary to obtain accuracy. 

The reason why only one-fourth of the space should be corrected 
for, becomes evident from the fact that in the first revolution of the 
telescope the error of the hair is doubled; and after reversing the 
instrument and revolving the second time, it is again doubled, but on 
the opposite side, so that the true direction lies exactly half way be- 
tween the two, and to correct for it we must move the hair one-half 
the space between the true line and one of the points. 

It is not necessary to level the instrument in order to make this; 
adjustment; but in case it is not leveled up, the observations must be 
made exactly at the intersection of the cross-wires. 

It must be remembered that the image at the cross-hairs is in- 
verted, and that in consequence the screws must be moved in appar- 
ently wrong directions. 

If there is any lost motion in the tangent screw, great care should 
be exercised in handling the telescope, so as not to influence its align- 
ment. 



THE A. LIETZ COMPANY. 6? 

Operation, Second Method. — Locate with the telescope three 
points in one direction, which are necessarily in a straight line, as long 
as the vertical movement of the telescope is in adjustment. Occupy 
the middle point with precision, and bisect one of the end points ; 
revolve the telescope and sight at the other end point. If this is bi- 
sected, the instrument is in adjustment ; if not, correct for it by taking 
up one-half the error. This method requires leveling of the instru- 
ment. 

Thus far we have been speaking of the vertical hair only, as it is 
the more important in a transit telescope. In a plain transit — that is,, 
one without a telescope level and without a vertical arc — the horizontal 
thread simply serves to define the middle of the vertical one, so that 
the observation may always be confined to a particular point in the 
latter. But if a level is attached to the telescope, then the horizontal" 
hair should be brought into the optical axis, before the level is set 
parallel to the line of collimation; otherwise, though adjusted for long 
distances, it will fail to be correct for short sights. 

Operation. — Set up the instrument near a house or fence and level 
up carefully. Clamp the telescope, and by means of its tangent screw 
bisect a point several hundred feet distant; then turn on center and 
mark a point on the house or fence, about ten feet distant. Now un- 
clamp telescope, reverse it, revolve on center, and again bisect the near- 
est point. Turn instrument on center and see whether the hair inter- 
sects the further point. If it does not, the correction must be made r 
by lifting or lowering the diaphragm by means of the upper and 
lower capstan-headed screws, until the bisections, after repeated trials, 
will coincide. 

5. The Telescope Level. — The object of this adjustment is to 
make the level parallel with the line of collimation. The principle 
underlying the method is : that points taken with the same angle of 
elevation or depression, and equally distant from the instrument, are 
of equal height. 

Operation. — Set up on a nearly flat surface and level carefully. 
On opposite sides, at equal distances, drive two stakes giving the same 
level-rod reading, with the telescope bubble centered in each instance. 
These points are necessarily on a level with each other. Now move the 
instrument to a point in line with both, and about ten feet distant from, 
one. Level up again. Take a rod reading on the nearer and then on 
the further stake. If they agree, the level is in adjustment; if not, 
move the telescope with its tangent screw over nearly the whole error, 






68 MODERN SURVEYING INSTRUMENTS. 

and sight again at the nearer stake and then at the further, repeating 
this until the readings are the same on both, when the telescope is truly 
horizontal. Now bring the bubble in the center of the tube by the 
correcting screws of the level, and the adjustment is completed. 

This adjustment may also be made in a room with the aid of a 
surveyor's level, with absolute accuracy. 

Operation. — A few feet (one or more) from each other set up 
the transit and level, each directed to the other. The cross-hairs of 
the level must be illuminated by a light, so that they shall become 
plainly and clearly visible through the transit. For this purpose cover 
the eye-end of the level with a bit of white paper and place a lamp 
behind it. Focusing both instruments properly will make the hairs 
appear very distinctly. Now, if both instruments are properly colli- 
mated, the level carefully leveled up, and the transit telescope of such 
height that we may view the interior of the level's tube, we are ready 
to adjust the transit telescope to a level plane, which is done by simply 
placing the intersection of its cross-hairs delicately over the intersec- 
tion of the level's cross-hairs. All that is required after that, is to 
center the transit's level bubble by means of the proper adjusting 
screws. 

This method recommends itself on account of its extreme sim- 
plicity. 

6. Zero of Vertical Arc. — This adjustment, once made by the 
instrument maker, is seldom vitiated. The object is to have the zero 
line of the circle agree with the zero mark of its vernier, when the 
level of the telescope indicates a horizontal position, and when the 
centers of the instrument are truly vertical. 

Operation. — The instrument must be carefully leveled by the 
small plate bubbles, and then the telescope by means of its level. This 
accurately accomplished, the vernier is shifted until the zero lines 
coincide. This must be carefully done, so that the instrument is not 
disturbed, and, when the vernier is fastened, care must be taken to 
allow a space that shall neither be too small nor too great between it 
and the vertical circle. In the first case it would bind under certain 
conditions of temperature, and in the latter the observer would not be 
able to obtain an accurate reading. The coincidence of the zero-lines 
must be made with a magnifying glass, and all parallax avoided. 

7. Centering the Field of View. — On some transit telescopes 
there will be found another set of four capstan-headed screws, exactly 



THE A. LIETZ COMPANY. 69 

alike to that which regulates the cross-hair diaphragm, and placed in 
a position quite close to it. These screws are for the purpose of direct- 
ing the tube of the eye-piece in such a manner that the field of view 
may be divided by the cross-wires into four uniform quadrants; that 
is, they enable the operator to so adjust his field that it may be bisected 
horizontally and vertically by the threads. In the Lietz transits this 
adjustment has been omitted, for the reason that the tubes are made 
of such length and with such care — being absolutely straight — that 
there is no need of displacing the field, after the line of collimation 
has been made to agree with the optical center, and the hairs are 
properly adjusted. The lines can never appear noticeably out of the 
field in our transits, and any additional movement in the parts of the 
telescope would neither be useful nor desirable. A first-class transit 
instrument can dispense with this arrangement altogether, and for 
this reason it is not usually found there. With an extra long telescope, 
however, there would be a slight advantage in being able to direct the 
field of view, for a possible fall of the instrument may so injure the 
tube that it could not be made absolutely straight again afterwards, 
and in consideration of this, we have adopted this correction only in 
the case of the 18-inch Y-level, which is the most liable to be damaged 
in that way. It alone possesses two sets of capstan-headed screws near 
the eye-end of the telescope — one for the adjustment of the cross-hairs, 
and the other for shifting the field of view so that it shall appear equally 
divided by them. 

Of the Y-Level. 

There are three principal adjustments. The spirit level must be 
parallel to the axis of collimation ; it must be at right-angles to the 
vertical axis of the instrument; the axis of collimation must agree 
with the optical axis. 

There are other instrumental requirements which belong to the 
instrument maker, however, and it is with the above three adjustments 
only that the surveyor has to deal, as they are likely to become dis- 
turbed in time. 

Before examining the adjustments, the sun-shade should be placed 
on the telescope, as it is only accurately in balance with this. 

ist Adjustment. — To set the spirit level parallel to the line of 
collimation, and, at the same time, place its axis in a plane with that 
of the telescope. It is best to attend to the latter first. 

Operation. — Turn the telescope so as to stand over two opposing 
foot-screws, clamp the instrument and bring the bubble to the center 



JO MODERN SURVEYING INSTRUMENTS. 

of the tube ; then rotate the telescope in its Ys, so as to put the level 
considerably out of a vertical — say about 15 or 20 degrees. If the 
bubble changes its position, it shows that the axis is not in a plane 
with that of the telescope. Correct it by moving the two side screws 
of the level case, until one-half of the deviation has been taken up. 
A few repetitions will insure accuracy, and destroy the side motion 
of the level. 

The level must now be made parallel with the line of the bottom 
of the collars. 

Operation. — Bring the bubble to the center of the tube; then 
reverse the telescope in the Ys end for end; do this carefully. The 
displacement of the bubble, if there be any, is the double error, which 
is corrected by taking up one-half of it by means of the adjusting nuts 
on the level case, and the other half with the leveling screws of the 
instrument. This operation is repeated until the bubble remains in. the 
center. 

To accomplish a proper adjustment of the level to the line of colli- 
mation, it becomes absolutely necessary that the collars be of equal 
diameter. We have already referred to the importance of even collar 
dimensions, and have laid great weight upon this requisite ; and here 
again we shall point out the errors to which a neglect therein may lead. 
A Y-level in such an event is not any better than a dumpy, and will 
have to be adjusted as such. 

Providing the Ys are filed out to the same absolute angle, the 
instrument may still be adjustable in all its parts : — the spirit level may 
be made parallel to the line of the bottom of the collars ; the Ys may 
be so adjusted that the bubble will remain in the center of the tube; 
the line of collimation may be brought to the center of revolution of 
the telescope; and this reversed end for end in the Ys, leaving the 
bubble in the middle, even if there be some difference in the diameter 
of the collars. It is the general opinion that after level, Ys and cross- 
wires are adjusted, the instrument must be correct. This is by no 
means certain, as the least difference in the size of the collars will 
throw out the line of collimation considerably. This difference is some- 
times found in new instruments, and is also produced by unequal wear, 
denting, etc. It is therefore advisable that the equality of the collars 
should be tested from time to time, which is done by a method given 
further on. 

2D Adjustment. — To place the level at right-angles to the vertical 
axis of the instrument. 



THE A. LIETZ COMPANY. 7 1 

Operation. — Turn the instrument so that the telescope shall stand 
over the line of two opposing leveling screws, and bring the bubble 
to the center of the tube; then turn the instrument 180 degrees on its 
center. If the bubble shows any displacement, correct one-half of it 
by means of the nuts under the bar at the Y supports, and one-half by 
the foot-screws. Several trials will make the correction perfect. 

3D Adjustment^ — To place the cross-web in the optical axis of 
the telescope, so that the intersection will remain on an object in 
revolving it. 

Operation. — Set the intersection of the hairs on a point about two 
hundred or three hundred feet distant, then revolve the telescope in 
its Ys half-way, so as to have the level case on top. If the wires have 
moved from the point, bring them back one-half of the amount of the 
displacement. Try again, and repeat the operation if necessary. 

The eye-piece may then be properly aligned and directed by the 
four black capstan-headed screws (nearest the eye-end of the tele- 
scope), so that the field of view shall appear evenly divided by the 
cross-hairs, as already explained. 

In this, as well as in any other telescope, we assume that the tubes 
are straight, the object-glass well centered, and the slide well fitted. 
If such be not the case, the telescope can only be adjusted for certain 
distances. It is urged by some makers that it is almost impossible 
to produce straight tubes, and that, therefore, the object-slide must 
be adjustable. This, however, is entirely erroneous. Perfectly straight 
tubes can be made, if the necessary time and money be expended, which 
is the only requisite. In a great many instruments sold today, you will 
find that the object-glass is not centered, that the slide is poorly fitted, 
and that all these inaccuracies, which are not apparent at a glance, 
prove more injurious than ever if the tubes are not quite straight. It 
must also seem clear to any one that the constant working of the slide 
in an adjustable ring would loosen the screws and cause considerable 
annoyance. 

Parallax is adjusted by moving the eye-piece in or out until a 
clear and distinct view of the cross-hairs is obtained, as in the case of 
the transit already described. 

The Collar Test. — After the instrument is properly adjusted, 
the equality of the collars may be ascertained in the following manner : 

Operation. — Make two bench-marks, place the instrument exactly 
midway between them, and find their true difference of level by reading 



*]2 MODERN SURVEYING INSTRUMENTS. 



leveling rods set upon them. Now place the instrument near one o 
the bench-marks and read the rods again. If the difference of the 
reading is equal to the true difference of level, the collars are of equal 
diameter, and the line of collimation is at right-angles to the vertical 
axis of the instrument. This test, once made, holds good ever after, 
as it shows that the collars are true, and consequently that a correct 
adjustment is assured of all its other parts, as already described. But 
it need hardly be mentioned that denting, the settling of sand particles 
and unequal wear will also affect the adjustment in the same manner. 

If the test shows that the line of collimation is not perpendicular 
to the line of the vertical center, then the collars are of unequal diame- 
ter, and the instrument is really nothing more or less than a dumpy 
level, as this defect deprives it of all the advantages for an easy and 
convenient adjustment, which characterizes the Y-level in comparison 
with the dumpy. 

This defect may, however, be temporarily remedied or adjusted 
in the same manner as the line of collimation in the dumpy level is 
adjusted, but it must ever thereafter remain permanently in its Ys, 
as it would, if reversed end for end, double the error which existed 
previous to this adjustment. 

The correction may also be made by displacing the horizontal 
cross-hair to the extent that the line of collimation shall be truly hori- 
zontal and, at the same time, parallel with the axis of the spirit level ; 
but, in that event, there will be no longer any agreement with the optical 
axis, which again gives rise to a number of inaccuracies that cannot 
be obviated. 

A Y-level, in order to deserve that name at all, must have equal 
diameters of its collars ; and if that is not found after a crucial test, 
the instrument maker should be called upon to remedy this dis- 
crepancy. 

No doubt can possibly exist in the mind of any engineer of the 
absolute necessity of the collar test. Considering the required parallel- 
ism of the axis of collimation and the axis of the spirit level, he must 
know that a contact can only be made between telescope and Ys by 
means of the collars, whose exteriors may either be parts of the surface 
of a cylinder, or that of a cone, and that the required parallelism is 
only possible in the former case. If one collar exceed the other in 
diameter, the centered level bubble, if reversed in the Ys, will indicate 
a displacement corresponding to four times the angle intercepted be- 
tween the collar axis and that of the spirit level. No further demon- 
stration of this fact is necessary. 



„ 



THE A. LIETZ COMPANY. 73 

Of the Dumpy Level. 

In principle, the same laws govern the requirements of the dumpy 
that hold good in the Y-level. Although its construction differs, the 
condition of its line of collimation, optical center and level vial must 
be such as to bear that universal relation to each other which we have 
fully explained in the other instruments. It is not difficult to make 
all the necessary adjustments properly, although it may not appear 
quite so handy to correct its errors as in the case of the Y-level. 
Once adjusted, however, the instrument will remain so for a long time, 
and it will give the operator considerable satisfaction, if used with the 
ordinary care. 

The adjustments of the level, and the telescope for collimation, 
will now be briefly mentioned. 

Put on the sun-shade, and focus the eye-piece until the hairs are 
distinctly visible and the parallax destroyed ; then proceed as follows : 

Operation. — Turn the instrument so that the telescope shall stand 
directly over the line of two opposing leveling screws, and draw the 
bubble to the middle of the tube by means of the foot-screws. Then 
turn the instrument on its center 180 degrees, and if the bubble remain 
centered the adjustment is perfect. Any displacement, however, will 
have to be corrected by taking up one-half of it with the capstan-headed 
screws attached to the level case, and the other half by the foot-screws. 
This operation must be repeated several times, in directions normal to 
each other — that is, over one set of opposing foot-screws as well as 
over the other, until the telescope may be swung in any position and 
the bubble will remain in the middle. See that the adjusting screws 
of the level vial are firm, yet avoid all unnecessary force in tightening 
them; all cramming is injurious, and tends to destroy the proper 
degree of refinement required. 

After having set the diaphragm so that the cross-hairs shall be 
absolutely horizontal and vertical, which is easily done by loosening 
the capstan-headed screws and turning the diaphragm slightly, being 
guided by some point bisected by the horizontal hair, we now proceed 
to adjust the cross-hair, which must be brought into the collimation 
line. Several methods are known; the one which is always available, 
however, is that by means of stakes and level-readings upon them, and 
it is to this that we shall confine ourselves here. 

Operation. — Choose a piece of ground nearly level, set up the 
instrument and center the bubble. Drive a stake (point i) firmly, say 
two hundred or three hundred feet from the instrument, in any con- 
venient direction therefrom. Hold the level rod upon it and take a 



74 MODERN SURVEYING INSTRUMENTS. 

reading. Now point the telescope in the opposite direction, the bubble 
being- centered, and plant another stake (point 2) at the same distance 
from the dumpy, driving it until the rod shall read the same as upon 
the first point. These two stakes are on the same level. Now set up 
the instrument abount ten or fifteen feet from the first stake, and bring 
the bubble to the center; take a rod-reading on point 1, and then on 
point 2. If the two readings are alike, with a truly centered bubble, 
the hair is collimated. If there is any difference, take up nearly all 
•of it by moving the diaphragm with the cross-hairs either up or down, 
as already explained. Repeat this operation until the readings on 
points 1 and 2 are identical, when the instrument is in adjustment. 

The vertical hair is of no particular importance. 

With these precautions, a dumpy level may be made absolutely 
accurate, and there is no reason why, for any of the land surveyors, 
and for nearly all of the engineer's work, this compact and steady 
instrument should not meet every requirement. We frequently discuss 
its merits with our customers, and have never hesitated to recommend it. 

Test of Telescopes in General. 

If a telescope is to be tested for its qualities, make sure that all its 
lenses are perfectly clean. 

To test for definition, use small, clear print, and view it from a 
distance of from thirty to fifty feet. If the print appears clear and 
well defined, and fully as legible at this distance as if viewed with the 
naked eye at the distance of distinct vision, the surfaces of the object- 
glass are perfect and well finished. If, on the contrary, the print ap- 
pears dull and indistinct, and the finer details illegible, or even invisible, 
the surfaces are imperfect and faulty, for the rays proceeding from 
the various points of the object are not refracted to their correspond- 
ing points in the image. 

Indistinctness may be caused by spherical aberration. 

To test this, cover the object-glass with a ring of black paper, 
reducing the aperture to one-half; again focus small print to distinct 
vision ; remove the ring of black paper and cover the center of the 
object-glass (previously left open), then mark how much the object- 
glass has to be moved in or out for distinct vision. If the spherical 
aberration has been reduced to a minimum, very little, if any, slide mo- 
tion is necessary to obtain a distinct view under both tests. The amount 
of movement, however, constitutes a measure for the spherical aberra- 
tion of the object-glass. 

Another test, but not as good as the one just mentioned, is to focus 



THE A. LIETZ COMPANY. 75 

an object to distinct vision; then slide the object-glass in or out, observ- 
ing at the same time the quantity of motion necessary to render the object 
indistinct. If the spherical aberration is completely corrected, the object 
should, theoretically, be rendered indistinct by the slightest motion of 
the lens ; but, practically, this is not the case, as the eye will accommodate 
itself in a measure to the difference of divergence of the rays, caused 
"by the motion, in or out, of the object-glass, in the same manner as it 
will accommodate itself to near and distant objects when viewing with- 
out the aid of lenses. So, if the image formed by a perfect object-glass 
is viewed by another perfect lens of long focal length, say six inches, 
the object-glass might be moved in or out one- fourth of an inch from 
the point of distinct vision, and the object will still appear compara- 
tively clear, as the one-fourth-inch motion, with an eye-lens of such 
long focal length, cannot cause enough difference in the divergence of 
the rays to prevent the accommodation of most eyes to it. The shorter 
the focal length of the eye-lens, the more rapid will be the change of 
divergence or convergence of the rays with a certain amount of motion ; 
therefore, the second test is only applicable with eye-pieces of very 
high power, which, at the slightest motion in or out, will cause a 
sufficient amount of divergence of the rays to prevent the accommoda- 
tion of the eye to the change. 

To test the chromatic aberration, either a celestial body or a white 
disc should be selected for an object. 

Focus the object to distinct vision, thereupon move the object-glass 
slowly in and out alternately. If, in the first instance, a light yellow 
ring is seen at the edge of the object, and in the second one a ring of 
purple light, the object-glass may be considered perfect, as it proves 
that the most intense colors of the prismatic spectrum (orange and 
blue) are corrected. 

To test the flatness of Held, take a square, flat object, the sides of 
which are about four inches long and perfectly straight — the best object 
is a heavily-lined square, drawn on white paper with india ink. Sight 
this object from such a distance that it will nearly fill the field of view 
of the telescope, and see if it still appears flat and its sides perfectly 
straight; if so, the telescope is a good one. If, on the contrary, the 
object appears distorted, i. c, if the sides, instead of being straight, 
form curves and the surfaces appear concave, instead of flat, the tele- 
scope is not good, for it shows that the proportions of foci, aperture 
and distances between the different lenses are not according to the laws 
of optics ; owing, generally, to the attempt to force the magnifying 
power beyond its limits. 



J$ MODERN SURVEYING INSTRUMENTS. 

As all the refractions of light in the telescope are caused by flat 
and spherical surfaces, it is evident that the edge of a round flat object, 
when used for the above test, cannot be distorted, but that the surface 
only will appear concave to a keen observing eye. A telescope which 
distorts the image to a perceptible degree will not, however, cause any 
errors in common use, if only one point in the lens is taken in all ob- 
servations, but it is decidedly objectionable in stadia measurements, 
where two points in the field of view are used at the same time. 

To Find the Magnifying Power of a Telescope. 

A practical method for finding the magnifying power, available to 
anyone, which does not require any apparatus, taking up only a few 
moments' time, is the following: 

Set up the instrument, and about twenty or thirty feet therefrom 
hold up a graduated rod. Observe the rod with one eye by direct 
vision, and with the other through the telescope. Assume a certain 
space on the rod, say the height of a numeral, or two sharply drawn 
lines, and count the number of divisions on the rod in that space ; then 
observe the number of divisions that are seen by the naked eye in the 
same space enlarged. The ratio between the two is the power sought. 
It is the reading of a magnified space of known length on the graduated 
face of the rod. With a little practice both eyes will be able to distin- 
guish the rod divisions at the same time. If what is known to be o.i 
of a foot, is enlarged by viewing it through a telescope so as to cover 
the space of 2.4 feet as seen by the unaided eye, the magnifying power 
is 24 for the distance in focus. The real power is somewhat less, for 
as the tube of the telescope is drawn out for near objects, the power 
necessarily increases. The magnifying power obtained by this method 
holds good for the distance that the rod can be read by the unaided 
eye, and it is always somewhat greater than the actual power. 

For a very accurate determination of the magnifying power, it is 
necessary to ascertain the focal length of the objective and that of the 
eye-piece, in order to compare them and to find their proportion. While 
the former is easily obtained by a direct measurement from the objective 
lens to the cross-hairs, the latter, usually containing an entire system 
of lenses, presents numerous difficulties. For this purpose we possess 
an apparatus, designed and built by a prominent optician in Germany, 
and which is perfectly adjusted to do its work. 

Dividing the focal length of the objective (when the telescope is 
focused to mean distance) in millimeters, by the equivalent gives the 
magnifying power of the telescope under consideration. 



THE A. LIETZ COMPANY. JJ 

If any our customers want the focal length of an eye-piece deter- 
mined, we shall cheerfully do so, without charge, upon receipt of it, 
which should be sent carefully packed by express. 

Adjustments of the Plane-Table Alidade. 

Without going again into all the details of instrumental adjust- 
ments, it behooves us to enumerate the points required of this instru- 
ment when in proper condition. These are : 

ist — That the fiducial edge of the rule be absolutely' straight; 

2d — That all parallax be destroyed, by placing the cross-hairs in 
proper focus ; 

3d — That the line of collimation move in a vertical plane ; 

4th — That this plane be normal to the plane of the ruler ; 

5th — That the same plane also intersect the fiducial edge of the 
ruler, or at least be parallel thereto ; 

6th — That during parallelism of the optical axis and the fiducial 
edge, the zeros of the vertical arc and its vernier correspond. 

This instrument is used in the topographical departments of the 
U. S. Coast and Geodetic Survey, and the U. S. Geological Survey, and 
is exclusively applied in mapping the topographical features of the 
country in Europe, usually by officers of the army, who control these 
surveys, after the triangulation points have been established. 

This method of surveying has been constantly improved in prac- 
tice, particularly by the experts of the Geological Survey, and it may 
be safely said that, with the required accuracy, nothing surpasses it for 
small-scaled work in speed and application. All the bulky parts of the 
table have been reduced to a minimum, so that it may be handled with 
comparative ease in the roughest mountain country. 

We refer our readers to appendix No. 22 of the Coast Survey 
Report of 1865, which may be had separately in bound book form, called 
The Plane-Table and its Uses, as an excellent theoretical and practical 
treatise of this interesting subject. 



Professional Papers 



PUBLISHED BY 



THE A. LIETZ COMPANY 

SAN FRANCISCO 



No. i. 



A SHORT AND PRACTICAL TREATISE ON STADIA 
SURVEYING, OR TACHYMETRY, 

With Tables for the Determination of Horizontal Distance 
and Elevation. 



Written for this Manual by OTTO VON GELDERN. 



The value of this method of obtaining distances is now so generally appreci- 
ated, that every engineer will use it in his work, wherever the accuracy obtainable 
is sufficient for his purpose. While it cannot replace the usual means of precise 
linear measurements employed in cadastral surveys, it offers many other advan- 
tages that cannot be too highly estimated. Under difficult topographical condi- 
tions the results, if carefully obtained, may be even better than those of the 
ordinary chain. At all events, the rapidity with which distances may be measured 
at all times, and its adaptability to inaccessible places, have given it that prom- 
inence in topographical work which it justly deserves. 

To make quick and reliable observations of this character, the instrument 
used should be a good one, and its telescope, above everything else, must possess 
power, definition and light in a high degree, in order to enable the observer to 
read the so-called telemeter rod with precision on long sights. 

The Principle of the Stadia Method. 

The fundamental basis underlying this method of measuring is well known, 
and is simply the geometrical proposition that parallel lines subtending the same 
angle from a given point, are proportional in length to their distances from that 
point. This explains generally the applied principle governing the stadia ; all 
the modifications of it are due to the structure of the instrument used, and to 
certain optical and geometrical principles that involve corrections to be introduced 
under certain conditions of sight. 

By placing two additional horizontal threads in the telescope, at equal dis- 
tances from the middle hair, we obtain a gauge that may be applied to a graduated 
rod, the intercepted space upon the rod increasing, as the distance between it 
and the telescope increases. If the graduation to some adopted unit of measure 
be so marked, that it may be read clearly and distinctly without error on longer 
distances, it is evident that a mere inspection of the rod by means of the tele- 
scope, will be sufficient to indicate its distance from the instrument. 

The threads may be inserted at random, and the rod marked to correspond to 
known distances ; or they may be placed so as to intercept one unit of measure 
on the rod to a given number of units in distance. The latter is that generally 
employed, and the usual ratio is 1 in 100. 

When the distance measured between two points is at an angle with the hori- 
zon, it becomes possible to determine the co-ordinates of horizontal distance and 
difference in elevation of the triangle, provided the angle of the slope is known. 
This may be read on the vertical arc of the instrument. If, in such cases, the 
telemeter rod be held at right angles to the line of sight, the horizontal distance 
will equal the cosine of the observed vertical angle, multiplied by the distance 
indicated by the rod. This must be corrected by certain small values, to which 
reference will be made further on. And similarly does the sine of the angle 
indicate the difference in elevation. 



82 



MODERN SURVEYING INSTRUMENTS. 



The usual custom here is to hold the rod vertical under all conditions, which 
is more readily accomplished, and, in certain localities, perhaps the only possible 
way of holding it. 

Optical Features and the Constants c and k. 

Certain optical principles do not admit of a stadia measurement from the 
point occupied by the center of the instrument, but from a point outside of the 
objective lens, equal in distance to its focal length. This gives rise to a certain 
value by which the stadia distance must be increased, and which may be prac- 
tically a constant for any length. It may be determined with sufficient accuracy 
by adding two measurements, taken with an ordinary scale or tape, from the 
object glass of the telescope, when the latter is focused to a distant object: one 
to the capstan-headed screws, holding the diaphragm with the cross-hairs, and 
the other to the center of the axis. The sum of these two (f -\-h, figure 1) is the 
constant c, which must be added to every horizontal distance, irrespective 
whether long or short. 




Tig.l 



In figure 1, let a = any rod reading, K = a constant expressed by the relation 
of the distance between the stadia threads and the focal distance of the object 
glass, then K a = d = distance from the focal point to the rod, for 

s : f : : a : d , or 
a f _,_„„._ f_ 
s 



(1) 



r herein 



represents the constant K. 



It must be mentioned, however, that this is not strictly correct, because the 
focus is changed with the distance of the object, and the value f therefore varia- 
ble. Nevertheless, the results, unless obtained on very short ranges, are as close 

as required for the purpose of the stadia, by assuming as a constant of any 

value that we may choose to assign it when we place the hairs, the ratio 1 : 100 
being usually adopted. 

To express the distance D of the rod from the point occupied by the instru- 
ment, on a level surface, we have, therefore, 

(2) D = Ka + c } 

remembering c as the constant expressing the distance from the center of the 
instrument to the outer focus of the objective, which must be added in every case. 
If K , as customary, equal 100 and c = 1.15' (as in the ordinary large transit), 
then D = 100 a -f- 1.15', so that the following rod readings would correspond to 
the distances as shown : 

1 foot = 100 ft. _|_ 1.15 ft. = 101.15 feet. 
1.69 feet = 169 ft- + 1.15 ft- = 170.15 " 
2.33 " =233 ft- + 1.15 ft- =234.15 " 
1 meter = 100 m. _j_ 1.15 ft. = 100.35 meters, 
and so on. 

Reduction of Elevated or Depressed Sights. 

If, now, the observation be made on a slope with rod held vertically, the 
angle of elevation or depression may be expressed by n, and the angle intercepted 
between the stadia hairs by 2 m. 

Any rod reading a may then be reduced to the reading en, or normal rod. 



THE A. LIETZ COMPANY. 83 

reading, by the following formula, which is obtained from the elements given in 
the diagram, figure 2 : 

(3) i 



cos n-\- l / 2 sin n [ tan (» -f m) -f tan (ra — w) ] 

Now, since the angle m in an instrument rated 1 : 100 only amounts to 17 
minutes, it is evident that the expression 

y 2 sin n [ tan (n + in) -f tan (n — m) ] 

is almost the same as sin n tan n, the difference being so small that it will not be 
noticeable at all in any of the stadia requirements, and writing sin 11 tan 11 in terms 

of the cosine, we have , and substituting in formula (3), it will reduce 

cos n 

to the simple expression 

(4) a x = a cos n. 

This, then, is the normal rod reading, which, by applying the constant K, 
gives the distance K a cos n, representing the hypothenuse h of a right-angled 
triangle, of which the horizontal distance d and the difference in elevation e are 
the co-ordinates. Their values in turn are proportional to the cosine and sine of 
the angle n, so that the distance 

(5) d = K a cos ~ ' n , 

and the elevation e = K a cos n sin n , which is 

(6) e = K a y> sin 2 n . 

(It is understood, in the case of the difference in elevation between the two 
points (e), that the middle hair touches the rod at a mark corresponding to the 
height of the instrument, as shown in figure 2.) 

Introducing, now, our constant c, which causes corrections also dependent 
upon the angle n , we must add to the horizontal distance d the value c cos n ; 
and to the elevation e the value c sin u , so that the corrected horizontal distance is 

(7) D = c cos n -f- K a cos 2 n, and the corrected elevation 

(8) E = c sin n-\-Ka x / 2 sin 2 n ; 

or, if the constant K = 100 , 

and the constant c = 1.15, 

then D = 1.15 cos*« + 100 a cos 2 n , 

and E = 1.15 sin « + 100 a ^ sin 2 n . 

If, for example, the rod reading a be 2.22 feet, and the vertical angle n = 20°, 
then 

D = (1.15 X cos 20° = 1.08) + (222 X cos 2 20° = 196.03) = 197.11 ft. 

E = (1.15 X sin 20° = 0.40) + 222 X { ^-^- = 71.35}= 71.75 ft. 

The second member of the equation is the important one, and that which 
characterizes the formula, the first being small and a constant for the same angle, 
independent of the distance. But as it cannot well be neglected altogether, it is 
customary — since it is not readily incorporated in tabular values — to supplement 
a table that shall furnish the values of d and e for different angles of inclination, 
by the terms c cos n and c sin n in a special place, usually at the bottom, where 
they may be readily found and applied. They vary so little from degree to degree 
that for the ordinary stadia measurements they may be entirely neglected. 

The annexed tables were calculated by the formulae 

d = K a cos ' n 
e = K a x / 2 sin 2 n , 

and so arranged as to give the distance d and the elevation e for every 2 minutes 




L "Height of Instrument u 



THE A. LIETZ COMPANY. 85 

of arc for a value of K a = 100, the rod held vertically. They admit of a simple 
application. 

By what has preceded, let it be required to find the horizontal distance and 
the difference in elevation, when the rod indicated 285 feet and the vertical arc 
10° 12'. Look for the column headed 10° ; run down this column with your 
finger to the figure on the same line with number 12 in the left-hand or minute 
column, where, for 100 feet, d is found as 96.86, and c 17.43. Multiply both of 
these by 2.85. This reduces the distance 285 feet to d = 276.05', and <? = 49.67'. 
At the bottom of the page will be found values of the corrections due to c for 
different focal lengths. Three values obtain: 1.90 (the large Y-level), 1.15 (the 
large transit), and 0.75 (the small transit). If a large transit has been used we 
look for the corrections corresponding to r = 1.15, and in the case before us we 
would obtain 1.13 and 0.21. These are added to the values already obtained, and 
we have : 

corrected horizontal distance D = 277.18 feet, 
and corrected difference in level E = 49.88 feet. 

The Stadia Board or Telemeter Rod. 

For stadia work an ordinary leveling rod may be used, and, with the aid of a 
pocket level (a so-called rod level with a circular bubble, that may be fitted and 
held to the edge of the rod), its vertical position may be assured. By employing 
two targets and reading them with care, the results will be as precise as the 
telescopic power admits. It is usual, however, in order to save time, to prepare 
a self-reading rod, so marked that it shall facilitate rapid observation and reduce 
all chances of error from a wrong reading. Many patterns are employed by a 
combination of geometrical figures and by different colors (red, black, white), 
that are intended to indicate at a glance the space between the upper and lower 
hair in terms of the rod measure. These patterns are either painted directly on 
a board from 10 to 12 feet long, that may be folded for convenience in trans- 
portation by a hinge in the middle, or on stiff canvas, in which case it may be 
rolled up for carrying in the pocket, and tacked to a suitable board whenever 
required. These so-called flexible stadia boards answer very well, but the former 
are to be preferred in accurate work, as they cannot be materially distorted by 
conditions of weather. 

In case the stadia hairs were set arbitrarily, it becomes a simple matter to 
ascertain the constant K. A distance of eight hundred feet or more is laid off on 
a level surface with a steel chain, and marked at each hundred feet. The in- 
strument is placed the distance of its constant c away from one of the end points, 
and readings are taken on a leveling rod at every hundred-foot mark. From 
these the ratio between distance and rod reading is readily determined. 

Or, a stadia board may be so divided that a unit of its measure shall agree 
with a hundred-foot space. If a blank board be held at every hundred-foot mark 
on the ground, we may draw upon it the intersection of the upper and lower hair 
for each station. If the rod units so obtained vary slightly from each other, the 
mean of them may be adopted without appreciable error, which is subsequently 
divided into smaller spaces, to read as close as desirable. In this wise we obtain 
a rod corresponding with the instrument of which it then becomes a part. 

Some instruments possess adjustable stadia wires. In that event the hairs 
may be set to suit the rod. 

In all these cases it is evident that the constant c must be previously deter- 
mined and properly applied. 

General Remarks. 

In making a stadia observation, after having set up and adjusted the transit 
over a point, direct the telescope to the rod and clamp the instrument in position. 
Move the telescope in a vertical plane, until the middle hair of the three inter- 
sects a line on the rod as high above the ground as the telescope axis is over the 
point occupied, and read the space intercepted between the upper and lower hair. 
An even foot-mark, or unit-mark, can always be found, upon which either the 
upper or lower hair may be placed, that will satisfy the conditions nearly under 



86 MODERN SURVEYING INSTRUMENTS. 

which a should be taken, and from it the rod may be read quickly up or down. 
To obtain the vertical angle, the telescope should then be moved either up or 
down with its tangent screw, to the exact intersection on the rod corresponding 
to the height of the instrument— which is 4.5' ordinarily — and the vertical arc 
read. 

There are occasions when the middle hair cannot be placed on the rod as 
explained — in the woods, for instance, when parts of the rod may be covered by 
leaves — and in that event we may read it wherever its exposed space permits, and 
make the necessary corrections afterwards. It is one of the particular advantages 
of the stadia that it may be used under very unfavorable conditions of the field, in 
forests, swamps, along declivities, etc., and yet obtain very reliable results. As 
long as the rodman is able to get to a place and to hold up his rod, and the ob- 
server can see a clear space on the face of it, the reading may be obtained that 
shall lead to the determination of the horizontal distance and to the difference in 
elevation. 

In cases where both stadia wires are not visible on the rod, the space between 
the middle hair and the visible one may be read off and multiplied by 2, it being 
presumed that the upper and lower are equidistant from the middle hair. But 
where very large vertical angles accompany the sight, however, it is not well to 
rely absolutely upon the result, for it is quite readily demonstrated that the 
horizontal distance will be either too large or too small by a quantity, that, in a 
rod-reading of 5, doubled to 10 feet, for instance, with a constant K = 100, an 
angle n = 40°, will come within about 4/10% of the correct value. With a ver- 
tical angle of 20° under the same conditions, the error in distance is about ' %. 
In the former case the correction would be plus or minus 2.43, and in the latter 
plus or minus 1.59 feet. But it shows that even under the most unfavorable con- 
ditions of sight we are able to approach the true distance within all the require- 
ments of topographical surveying. 

A survey may be made with the stadia altogether, or it may be preceded by a 
triangulation, in order to locate a number of fixed points — the relative elevations 
of which are established with a leveling instrument — between which the topog- 
raphy is filled in with the stadia. The latter method is necessarily more trust- 
worthy, and should always be adopted where large areas are to be surveyed; but 
if the engineer is pushed for time, he may omit the triangulation and yet obtain 
very good results. In such an event great care should be exercised in locating 
the turning points. Occupying point 1 and observing upon point 2, read carefully 
the azimuth on the plate, and check it by recording the bearing of the needle 
also. Read your distance from the rod and record that. Having placed the 
middle horizontal hair on the rod as high above its foot as the telescope axis is 
over point 1, observe the vertical angle, which is either plus or minus, and note 
it down. Leaving point 1 and proceeding to point 2, set the instrument over the 
latter and level up. It may be clamped upon any desired known azimuth, but the 
reading of the plate should not be omitted in a direction toward point 1. Record 
this with the bearing of the needle, which will give the reverse course of the 
sight 1 to 2. Observe again the distance between the points as shown by the 
rod, and note it down, as well as the vertical angle from 2 to 1, as explained, 
which should give the same result as before with reversed sign. These precau- 
tions of observing twice between turning points form a very valuable check, and 
should never be omitted where every other datum is lacking and the stadia 
method alone is relied upon. After having taken his back-sights, the surveyor 
proceeds with the observation of all intermediate points required for his topo- 
graphical details, before locating point 3 for a further advance. 

Work may be done still more rapidly by occupying every other point only ; 
but in that case the bearings of the lines are solely obtained by the needle, and 
there is no check. 

By employing two or even three rodmen, distributed about the field as ad- 
vantageously as possible, the engineer is able to observe rapidly without loss of 
time. It is always well to have a recorder accompany the party, whose sole duty 
it becomes to note down the observations of points, and the description as to 
what these points represent. If necessary and desirable, a small drawing-board 
may be taken into the field, and, instead of a recorder, a plotter may be employed, 
who lays down the reduced observations as the work progresses. This is con- 



THE A. LIETZ COMPANY. gy 

siderably slower, but it offers the advantage of a completed field map when the 
survey is finished. 

Instead of employing the tables here give, the reductions may be quite ex- 
peditiously and accurately made in the field by means of the logarithmic slide 
scale, which the author employs in his surveys altogether, a description of which 
is readily obtained. 

With a little practice the engineer will work himself into the use of the 
stadia, and become an expert. Tachymetry, as it is called, is an indispensable 
method of measuring, and one that the surveyor of today must acquire. 

Considerable might be said regarding useful hints and instructions for the 
field, but we prefer to let every engineer find his own method in the practical 
application, knowing well that after he has mastered the principle, he will adopt 
a system of work best suited to his requirements. 

The essential requisites for a successful operation are a good clear telescope, 
affording a distinct view of the rod on long ranges (the author prefers the in- 
verting eye-piece, as one affording better light and a more distinct image, there 
being no particular advantage in seeing objects erect, as the mind soon accus- 
toms itself readily to an inverted vision), a steady instrument, and, for the 
method under discussion, a true vertical rod. * 



88 



MODERN SURVEYING INSTRUMENTS. 



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No. 2. 



REMARKS ON THE PRINCIPLE OF THE LOGARITHMIC 

SLIDE SCALE. 

Written in 1885, but entirely revised for this Manual in 1893. 



By HUBERT VISCHER, C. E. 



The employment of mechanical devices for performing computations has 
attracted the attention of arithmeticians for a couple of centuries past, and to no 
class of persons is it of more direct interest than to those engaged in technical 
callings. These endeavors have been pursued upon several distinct lines, and we 
may notice by way of classification : 

1st. The endeavor to perform desired arithmetical operations by devices 
distinctly mechanical in their nature, seeking by skillful combination of me- 
chanical elements to carry out the ordinary sequence followed by the computer in 
making the calculation. We may here mention the celebrated machine of Bab- 
bage ; and as a more recent illustration, the "Arithmometer" of Thomas, an 
instrument of only moderate cost, and one coming constantly into greater use. 

2d. The use of geometrical figures representing the mathematical relations 
existing between mutually dependent quantities. This method, first suggested by 
the development of the Des Cartian geometry, has, in very recent times, been 
developed into a new science, graphostatics — which does not merely seek to 
present the deductions of analytical reasoning graphically, but starting at the 
elements, builds up methods of its own in which the arithmetical conceptions of 
magnitudes fall more and more into the background and are replaced by opera- 
tions which are mechanical in application, if not in their conception. 

Besides these two methods, we have another, somewhat partaking in nature 
of both, yet embodying a distinct principle of its own, that of the Logarithmic 
Slide Scale. 

It is here proposed to take a cursory survey of this field, which is of wide 
application and certainly of interest, being an important agent for the saving of 
time-robbing computations. It is worthy of more general attention than it has 
received in this country; though in Europe, the slide-rule is recognized as the 
engineer's daily pocket companion. 

The-^lide-rule rests upon two most simple principles: first, that magnitudes 
in general may be represented by the length of lines ; second, that these lines, 
when measured off upon one another, may represent by the length of a resulting 
line, either a summation or a difference of the magnitude which the lines repre- 
sent. The first principle is made use of in the logarithmic graduation of the 
scales ; the second principle finds application in the sliding motion which we 
impart to the scales. Slide-rules have been constructed of many kinds and for 
many special purposes, but they will all be found to reduce to these two ele- 
mentary principles. 

The use of the logarithmic graduation here, as in all other cases where 
logarithms are employed, is due to the desire to reduce arithmetical calcula- 
tions by one step in the scale of operations; thus replacing multiplication and 
division by addition and subtraction, and reducing involution and evolution to 
multiplication and division. 

The method in which the logarithmic graduation is carried out is explained 



THE A. LIETZ COMPANY. 93 

most easily by taking a special case, and we refer to the scale AB A'B' on Fig. 1. 
The length of this scale, measured between the two extreme outer limits, marked 
1, 1, is assumed as a unit of length; and what the absolute length of this unit is, 
is perfectly immaterial. We may, for purposes of illustration, assume it to be 
just one foot long. As a preliminary step, let us first imagine this length 
divided off into say 1,000 equal parts. Before proceeding further, however, let 
us recall to mind the well-known property of "periodical repetition" peculiar 
to the Briggs system, whereby all numbers represented by the same numerals, 
grouped in the same order, are represented by the same logarithm, independent 
of the characteristic or mantissa. 

It is clear that with the aid of a table of logarithms and using our scale of 
equal divisions, we may at once assign to any logarithm in the table a place on 
the scale, such that its distance from the zero (or left-hand end of the scale), 
may correctly represent the value of the logarithm, plotted in our unit or 
standard of length. Doing this for all logarithms, commencing at the number 
1, and progressing by any suitable interval (say 1-100 of unity), let us mark 
each so determined point by a cross-line on the scale, and (in order to preserve 
it for future use) mark opposite the cross-line the number corresponding to the 
logarithm which the cross-line fixes. 

Having done this, we reach the right-hand end of our scale, when in our 
table we reach the number 10. It is apparent that our scale represents graph- 
ically a table of logarithms for all whole numbers between 1 and 10, with 
suitable subdivisions, and corresponds in all particulars to the printed table from 
which it was constructed. But it is equally clear that if we agree to consider 
the scale as representing the fractional part of the logarithm only, and without 
reference to the "characteristic," we may at once extend its range so as to em- 
brace the whole field of positive numbers without any reservation. The 
"characteristic" of the logarithm, however, only determines the position of the 
decimal point in its number. Therefore, this stipulation about dropping the 
characteristic implies, conversely, that our scale shall only give us the numerals 
which express a number, without reference to a decimal point ; so that, if we 
read 2, 3, 5 on the scale, we may read this as 235, or as 235 with any number of 
zeros affixed or prefixed to it; as 0.00235 or as 2350, for example. In slide-rule ^ 
calculations there must always be some foreign means employed for correctly 
assigning the position of the decimal point, a matter which will be referred to 
again later on. 

It is now practically shown what constitutes the construction of the loga- 
rithmic scale, — only one, however, of an infinite variety of possible logarithmic 
scales. Any series or group of numbers may be made the basis of a similar 
scale. Thus, by means of their logarithms, we may construct logarithmic scales 
for the natural sines or tangents of angles (see scales E and F, Fig. 2), or for 
any other function of angles ; or, as the choice of the length of our unit was left 
perfectly open, we may plot scales to any enlarged or reduced scale, which latter 
observation is important, as it forms the basis of all operations embodying 
involution and evolution in the slide-scale calculations (as will at once appear 
clear by remembering that these operations, logarithmically speaking, imply 
multiplication and division). 

Returning, however, to our constructed scale, Fig. 1, let us conceive it 
severed longitudinally along its central line by a cut, a b, so as to fall into two 
identical scales, AA' and BB'. Furthermore, let us regard these scales as free to 
slide laterally to the right or the left, along their common line of contact, a b. 
With this motion we at once obtain the means of performing any desired multi- 
plication or division. This is clear, if we consider that the divisions upon our 
scale are magnitudes logarithmically plotted, and that, therefore, an addition or 
subtraction, as far as these are concerned, executes a multiplication or division; 
as regards their numbers (which are, by-the-by, the only records on the scale). 
With this capacity of motion, we have attained the simplest form of the slide-rule. 
A single setting of the slide performs a multiplication or division ; if desired, a 
combination of both, i. e., a proportion ; and in many cases not simply for a single 
set of numbers, but for a whole series of sets of numbers at one and the same 
operation. The details of manipulation are not entered into here, having only 
the principles of the slide-rule in view. If desired, these can all be found de- 



94 MODERN SURVEYING INSTRUMENTS. 

scribed at length in the printed directions furnished with the scales. Be it 
remarked, however, that although the whole operation has been essentially a 
logarithmic one, we lose sight entirely of logarithms having been used at all. 
This is always the case in operations with the slide-rule. In fact, the peculiar 
merits of the slide-rule can hardly be better expressed than by pointing out this 
unconscious gaining of all the advantages of using logarithms, while saved the 
labor of taking them from tables. While the whole conception of the slide-rule 
is logarithmic in its nature, save as a means of understanding its construction 
and in studying out particular modes of application to meet special cases, this is 
lost sight of entirely in its use. 

The slide-rule, as constructed by the firm of Dennert & Pape (in Altona, 
Germany), is shown in figures 1 and 2; the latter being an isometrical view of 
the scale in order to better show its working parts. These are as follows : A 
thin slab of boxwood, called the "slide," upon the edges of which two scales, B 
and C are engraved. The slide being fitted with tongue-and-grooved edges at its 
sides, is free to move between two other boxwood surfaces also bearing scales, 
A and D. The latter are parts of the same piece of wood, being connected with 
each other underneath the slide, and both of these (together with the connecting 
boxwood member) form the "rule," into which the slide is recessed laterally while 
left perfect freedom of motion lengthwise, in both directions. Scales A and B, as 
has been shown, are exact duplicates of one another, as are also scales C and D, 
thus forming two pair of scales. The latter pair, in principle of graduation cor- 
respond to the former pair entirely, but are graduated to one-half the scale (or 
length of unit) of A and B. This reduction in scale would make each of the 
upper scales one-half the length of the lower pair, were it not that we utilize 
the remaining half by engraving thereon another duplicate set of the smaller 
scales, placed alongside of the former; thus making the total length of the upper 
double pair exactly that of the single lower pair. Each half of either "double 
scale" is not to be regarded as separate from its neighbor, but as joined to it, 
so as to form one continuous scale ; the idea being to allow the double scales to 
represent all numbers for an interval of two whole powers of 10, while the lower 
scales represent all numbers for half that interval ; if the lower scale embraces, 
.for instance, the period from 1 to 10, then the upper similarly represents the 
period from 1 to 10 on the first (or left hand) halves, while the second (right 
hand) halves simultaneously represent the numbers from 10 to 100. The pair of 
scales on the slide (though movable as a pair) stand permanently with their 
extreme ends directly over and under one another; so also stand permanently 
fixed opposite one another the ends of scales A and D. 

Now, while the double scales C and D, on account of their lateral motion 
along their common line of contact, answer the same purposes exactly that the 
lower pair do (that is, perform multiplication and division also), a little reflec- 
tion and study of the figure will show how, regarding A and D or B and C as 
pairs, the following must always hold good, on account of the peculiarities of 
the mode of graduation : any number on the upper scale stands directly over its 
root on the corresponding lower scale ; and conversely, any number on a lower 
scale may be raised to the second power by taking the corresponding number 
exactly above it in its companion scale. Thus a simple transfer made in a suit- 
able manner, from either scale to the other, at right angles to the axis of the 
rule, effects an involution or a radication to the second degree ; and either of 
these operations may be combined, at will, with multiplication and division, by a 
suitable movement of the slide.* Involution and evolution to higher powers may 
also be executed by the slide-rule, though we merely note the fact here. 

The "slide," however, can be completely run out of the rule and re-inserted, 
when so desired, reverse side up. The reverse side of the slide bears two scales, 
E and F, these being respectively logarithmic scales of natural sines and natural 
tangents. The reverse side of the slide also carries a third scale, G, bearing 
equal divisions (l-1000ths of the scale length) and answering the purpose of a 



* To accurately effect this transfer, a small brass part, called the "runner," is provided. 
See Fig. 2, A. This slides freely along the rule in grooves on its outer sides, and carries two 
indices, a, a, which accurately transfer points from one scale to another. 



THE A. LIETZ COMPANY. 95 

table of ordinary printed logarithms, in which the numerical value of any loga- 
rithm may be directly read off the scale. f 

With the slide in the reversed position, the slide-rule presents the appear- 
ance shown in Fig. 2. When used in combination with each other, scales A, D, 
E and F enable us to perform any calculation into which enter the trigonometrical 
functions of angles, combined in any way, by multiplication, division, involution 
or evolution, with quantities expressed in simple numbers. 

Our slide-rule, now fully equipped, is an instrument only a few inches long,$ 
suitable for being carried in one's breast pocket, and of but trifling cost. To 
enumerate its various uses, it at once serves as a table of numbers and their 
squares and cubes, their square and cube roots ; it is at the same time a table 
of common logarithms of natural sines, cosines, tangents and cotangents. It is 
moreover capable of mechanically combining any of the above functions in any 
desired arithmetical combination, constantly showing up to better and better 
advantage the more complex the nature of the combination is. It serves also as 
a convenient pocket rule and straight edge, for it is both of these. It further- 
more contains printed on its reverse side a valuable list of useful pocket data of 
many, frequently used, practical coefficients. Yet while being all these things 
combined, alas, absolute perfection is unattainable ! It must be admitted it has 
its shortcomings also. Owing to the mechanical difficulty of graduation, and the 
uncertainty of reading results closer than to the third (at times the fourth) 
numeral place, it remains, notwithstanding all its theoretical perfection, practically 
an instrument only applicable where no greater accuracy than the third or fourth 
figure is required. 

Its use must always be a judicious one. The banker, computing interest or 
exchange upon extended rows of figures, will find the slide-rule falls short of 
his requirements. Its accuracy is inadequate in many calculations of the engineer, 
and many have undoubtedly cast the slide-rule scornfully aside, only half exam- 
ined, on account of the only approximate accuracy of its determinations.* 

These shortcomings freely admitted, it still remains an invaluable assistant, 
and serves to good purpose wherever a limited degree of accuracy is required — 
and this, after all, holds good in the vast majority of cases in engineering prac- 
tice. In construction; wherever we have to deal with practical coefficients (gen- 
erally themselves but approximations) ; where, moreover, wide factors of safety 
are generally introduced, and where, after all, practical considerations usually 
dictate a selection of the nearest marketable standard size — here, always, the 
slide-rule gives us results quite as reliable as the most elaborate calculation car- 
ried out to the fifth or sixth decimal place. In estimates of earthwork, where our 
surveys are at best but close approximations to the true condition of the ground ; 
for proportionately distributing minor errors ; for interpolating intermediate 
grades ; for at once transforming quantities expressed in one standard unit to 
equivalents in another standard — for all these purposes, on account of its great 
rapidity and freedom from liability to "mistakes," the slide-rule cannot be too 
highly estimated. 

It may not be equal to figuring out traverses to the one hundredth, or the 
one thousandth parts of a foot (and how very seldom do our measurements really 
warrant such subsequent super-refinements in calculation) ; yet even here it may 
do good service as a check against "mistakes." There are hundreds of cases 
where its use in the field may obviate the many half hours and quarter hours 
consumed — with a party standing idle all the time — while one man alone is busy 
figuring out some field problem of location. We have, besides these cases, another 
frequently recurring set ; namely, where the relations expressed in an equation 
are so complex as to make solution only practical by continued approximation ; 

f Scale G is really the scale of imaginary equal divisions first referred to as a preliminary 
step towards graduating our original sacle, A, A'. 

± Generally 26 centimeters, or 10 inches. 

* Notwithstanding the above remarks, those who really make a study of it, will be 
astonished at the accuracy it can be made to yield in the hands of an adept. The slide-rule, 
namely, often contains in itself the means of overcoming its own deficiencies. Thus used, 
the ordinary limit of the third of fourth numeral place falls away, and that of the sixth or 
seventh place appears as its limit in its stead. For instance, any rapidly converging series 
applied to the rule extends its range at once immensely. This study of the ultimate possi- 
bilities of the slide-rule and its special applications is a highly interesting one to any one 
with leisure to devote to it. 



g6 MODERN SURVEYING INSTRUMENTS. 

or where we have to assume coefficients, themselves functions of the element to 
be determined; where, assuming some probable value of the required quantity, 
we gradually, by successive trials, adjust all elements to conformity, as so fre- 
quently occurs in hydraulic work. Here we can always use the slide-rule advan- 
tageously for the first stages of the calculation, and when tolerably certain of 
being "near the mark," we can then resort to ordinary modes of calculation in 
the last and final stage. 

From what has been said of the general accuracy of the slide-rule, one impor- 
tant corollary should be drawn : to use it successfully, that is, rapidly, we should 
never waste time in straining at the last hair, either in setting the scale or iir 
reading a result ; this will reap no adequate return for the extra labor spent. f 

One of the chief difficulties to beginners in using the slide-rule lies in assign- 
ing to a result its correct local value ; that is, to fix the position of the decimal 
point. Many do this by rule of thumb entirely, placing the decimal point by guess- 
work, whereby mistakes are liable always to creep in. The most satisfactory 
method is to preserve in one's head the logarithmic characteristic separate, and to 
execute mentally the operation implied by the calculation, regarded as a loga- 
rithmic problem. The result of this simple calculation always fixes the local value 
of the result correctly. For example, say 230 is to be multiplied by 0.0003, and 
the result divided by 2.7. Then we have 230 [characteristic -f~ 2], 0.0003 [charac- 
teristic — 4], 2.7 [characteristic 0] ; then + 2+ (— 4)— 0=+2 — 4 =— 2. 
The slide-rule gives the figures of the answer to four places, 2555 (the last place 
a little uncertain), and from the foregoing we know the correct value of 
230 -i- 2.7 X 0.0003 to be 0.02555. An additional unit must, however, always be 
added or subtracted every time we have to resort to a substitution of one index 
for another in attaining a result, or when we read a result by passing through 
an index (which corresponds entirely to carrying a unit or borrowing one where 
ordinary logarithms are used). A little practice, however, teaches us how this is 
to be applied. To illustrate : 56 X 7 = 392. If not modified, our rule would give 
us 1 -f- = 1, or 39.2 as an answer. To obtain a reading at all, a substitution of 
the indices was required, for which a unit must be added, when we have 
1 -}- -j- 1 = 2, giving the correct result 392. Or, say we inquire how often 7 
goes into 56. For the position of the decimal point, we would have 1 — 0=1, 
or the answer, 80 times. We had, however, to use the right-hand index to obtain 
a reading, where ordinarily the left-hand index would have given us the answer. 
This substitution implies our subtracting an additional unit, and we have 
1 — — 1 — 0, or 56 -r- 7 = 8, the correct answer. 

This calculation is never too difficult to be kept in one's head, save where the 
operation is a lengthy one, when it is well to keep the characteristic, as was done 
above in the process of illustration, on a separate scrap of paper, or to provide the 
slide-rule with some distinct recording device for keeping the characteristic. A 
simple device for this purpose is that of Mr. Deering, of the Southern Pacific 
R. R. A small annular disc, free to revolve around a center, upon which a radial 
scratch used as an index is marked, is provided with several radial divisions to 
either side of a central initial mark or zero. The disc is turned a suitable number 
of places to the right or left to record the characteristic, when the slide is set to 
the number and its position shifted appropriately at each stage of the operation ; 
the index on the fixed center finally indicating the correct position of the decimal 
point. This little device is mounted On the runner of the slide-rule, and can be 
easily turned with the finger while one manipulates the runner. 

We will now close our observations on the ordinary slide-rule, remarking that 
figures 1 and 2 are only illustrative representations of the rule, and only show the 
main subdivisions. An idea of the fineness of the graduation actually used may 
be derived from figures 3 and 4, which show the same rule with the runner 
removed, reduced to about four-fifths the usual size. 

Besides that of Dennert and Pape the slide-rule of Le Noir has been widely 
introduced into this country, which, although apparently differing but slightly 
from the former, falls much short of it in practical efficiency. The most essential 
difference consists in its having three of the "double scales/' and only one single 

f In using the scale this is essential, as also that the slide should move with perfect free- 
dom, though not so freely as to slip by an inadvertent touch. To effect this, keep the 
grooves clean, and, if necessary, lubricate with a drop of fine oil. - 



THE A. LIETZ COMPANY. 97 

scale, instead of two of each kind — and there is no runner. Slight variations in 
the arrangements of the slide make great differences in the degree of service- 
ability. 

The slide-rules already described are applicable generally to all calculations, 
and there is no calculation which cannot be executed by carrying out with the 
rule, step by step, each successive intermediate operation necessary to attain the 
result. This, however, often necessitates several settings of the scale, in order to 
obtain a single result. To avoid this extended manipulation, special slide-rules 
may be constructed, capable of solving almost any such case by one single, or at 
least by a greatly reduced number of settings of the rule. 

Speaking generally, any function of two variables combined with constants, 
may be solved by one movement of a specially constructed rule, the peculiarity of 
the special construction being that the constants are embodied in a suitable man- 
ner with the variables directly. With each additional independent variable above 
tzvo, one more movement is required, generally necessitating the introduction, 
however, of an additional scale. 

Figure 5 gives an illustration of this kind, showing a scale very widely used 
in Germany in topographical work. With stadia measurements for direct read- 
ings of a vertical rod, we have the formulas : 

d = K a cos ~ li , 
c = K a y 2 sin 2 n , 

where n is the angle of elevation above the horizontal ; K, a constant dependent 
upon the construction of the telescope, and generally so adjusted as to be exactly 
100; a, the reading on the vertical rod between the stadia hairs; d, the corrected 
distance of the observed point from the instrument ; and e, its elevation above the 
horizontal plane through the horizontal axis of the telescope. 

In this form of slide scale, we have the slide bearing two scales ; the upper 
scale graduated to ^ sin 2 n, the lower one for cos 2 n. The rule carries two 
identically graduated scales of simple numbers representing the rod readings, a. 
Setting the index of the lower scale to coincidence with the rod reading, we read 
directly on the lower scale opposite the observed angle n, the corrected, i. c, hori- 
zontal distance d, also on the upper scale, the difference in elevation, e. 

This scale is very serviceable,* but as usually constructed is too long to be 
convenient for anything but office use. There is another scale for the same pur- 
pose, executed in metal, fitted for being used in the field, a vernier being employed. 
In this case, the finer metallic graduation is relied on to make up in accuracy what 
otherwise would be sacrificed by the reduced length of the scale. 

Another direction presents itself for development of the slide-rule by arti- 
ficially extending the length of unit (without correspondingly increasing the size 
of the instrument). In his catalogue of instruments, Stanley of London, describes 
an instrument by Professor Fuller. Here, by developing the scales on a spiral 
line upon a cylinder, a length of unit equivalent to 83 feet is attained, of course, 
hereby very materially increasing the accuracy of the slide-rule, although probably 
not nearly in the ratio of the increased length (which is about one hundred-fold 
that of the ordinary slide-rule). 



* This scale is also very convenient in running grade lines, enabling the transit-man 
always to select his grade points on the ground, and keep track of his elevations without the 
aid of the level, and judiciously used will often save much "backing up" in field location. 



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No. 3. 



SOME PRACTICAL HINTS ON HOW TO TELL A GOOD 
SURVEYING INSTRUMENT.* 



By A. LIETZ, Member Tech. Soc. 



There are, indeed, many improvements, which may yet be added, but 
if they are not made in a thorough workmanlike manner they are of little, if any, 
importance, and will in no case make an instrument of fine quality. 

Graduation. — In a transit, the graduation is the most important part. Solid 
silver is the best metal known, upon which a perfect graduation can be made, and 
it is therefore almost exclusively used by makers. It has the advantage of keep- 
ing its surface better than the silver wash, which is found on most of the older 
instruments. 



To examine the graduation, the first thing should be to see whether each line 
is perfectly sharp and clearly cut ; for this purpose it is well to use a compound 
microscope, as only a very keen observer will be able to detect unevenness in the 
lines with a common magnifier. The starting point of a line, if closely examined, 
will show whether a perfectly-shaped and well-set tool was used in cutting it. 

The line shown in figure A, in which the upper or pointed end is the starting 
point, indicates by its true shape that it could only have been made with a perfect 
and properly set tool. It is a fact that this shape is found in all graduations of 
first-class instruments. 

In Fig. B the line has no taper, but begins with its full width. In such an 
event the cut was either made from the inner rim of the circle outward, or, what 
is more likely, the engraving tool was set end for end and drawn from the start- 



* Reprinted and revised, by permission, from the Transactions of the Technical Society 
of the Pacific Coast, Vol. VII, No. 5, December, 1890. 

LOFC. 



100 MODERN SURVEYING INSTRUMENTS. 

ing point backwards toward the center. In most cases is the blunt end of the 
line explained by the latter method. Although the tool used for such a purpose 
may have been sharp and of the proper form, the additional pressure required to 
draw it with its wrong end foremost vitiates the degree of accuracy of the gradu- 
ation, for, if an unnecessary force is applied in producing a line, the tool will not 
always follow the motion in which it is guided by its drawing mechanism. 

Figure C represents a line made with an imperfect drawing device and a dull 
tool not capable of doing good work. 

It will be noticed in figures A, B and C, that the starting point of the line 
shows the shape of the tool with which it was made, and this is, therefore, the 
main point upon which to pass judgment on the value of a graduation. 

After we have convinced ourselves that the shape of the line is perfect, we 
may feel somwhat assured that the graduation is a good one ; but if the lines are 
not equally spaced, they are worthless. To determine this is the most difficult as 
well as the most tedious of tests to be made in the examination of an instrument 
with graduated circles. The manufacturers have apparatus with which such 
examinations can be made in a comparatively short time, and with a great degree 
of accuracy. No maker of first-class instruments will let one go out of his hands 
before having convinced himself that the divisions are as perfect as demanded by 
the character of the article. 

The most accurate graduation, however, is of no value without a well-fitting 
center. To prove both, several methods are employed. The surest test is to 
clamp the vernier plate to any point of the circle, then, if by adding the reading 
of the two verniers together — frequently repeating this manipulation upon differ- 
ent parts of the circle — the sum will always be 180 degrees, they are correct. 
(This refers to plates graduated from to 180 degrees, on both sides of zero; in 
case of a graduation to 360 degrees, a subtraction is required.) 

The graduation of an instrument having but one vernier can only be tried 
with the telescope, which is a rather tedious operation. 

It may also be remarked, that short lines on a graduated circle are of some 
advantage, as the spaces between them appear to be much larger, and there is 
consequently less fatigue to the eye while reading. It is anothr fact that during 
the process of graduating the tool is not required to do as much work, and is 
therefore apt to keep its fine edges better, thereby securing more perfect work. 

The space between the circle and verniers must be very small if an accurate 
reading is to be obtained ; it must appear through a reading glass like a very fine 
black and uniform line, and should remain so during the revolution of the circle. 

In second-class instruments it is generally found that the verniers and circles 
are not set in the same plane ; this is done to make any unevenness in the plate 
disappear, but it is a very objectionable feature, for it will cause parallax, and no 
accurate reading can be taken with such circles. 

The Telescope. — The telescope forms a very important pait of an instrument, 
and must, therefore, be closely examined. The reason why so many telescopes of 
second-class instruments are called good is because they have a very low magnify- 
ing power, and consequently will give a good definition; but if the magnifying 
power of such telescopes were to be increased to what it should be, with the same 
kind of glasses and workmanship, the definition would be entirely lost. Experi- 
ence has shown that a telescope oi W/2 inches length, such as is generally used in 
transits of the ordinary size, may have a magnifying power of twenty-four diame- 
ters, and give a good definition and sufficient light, if the new Jena glass is used ; 
while most telescopes of the same size, which I have had occasion to examine, 
show, on an average, a magnifying power of fifteen diameters only. It is true 
that a low power may be of advantage under certain atmospherical conditions, but, 
as a rule, a higher power will give better satisfaction if the lenses are first-class. 

Inverting telescopes, which are used almost exclusively in European coun- 
tries, are comparatively little in vogue in the American engineering fraternity. 
They have a great advantage over the erect telescopes ; the eye-piece having two 
lenses only and being shorter, the proportion between the focal lengths of the 
objective lens and the eye-piece may be increased considerably, and thusly the 
magnifying power, without loss of light. 



THE A. LIETZ COMPANY. IOI 

Construction. — In regard to the construction, it is the aim of every maker to 
build an instrument of the least weight, it being limited only to the extent that it 
shall not be affected by the wind and become unsteady by reason of its lightness. 
While it is reasonable that a proper reduction can best be effected by decreasing 
the size of the whole instrument, instead of reducing the weight of individual parts 
of a large transit, for instance, great possibilities in this direction are open by a 
judicious use of aluminum in the manufacture of instruments. The author 
firmly believes that with this metal we shall be able to reduce the weight con- 
siderably without any sacrifice of steadiness, and it is his purpose to make some 
detailed investigations in the near future that shall lead to an intelligent under- 
standing of this subject. 

The steadiness of an instrument depends upon its construction ; those that 
have the longest centers, with the shortest distance between the tripod-head and 
the plates, and in which the distance between the leveling screws is large enough 
to secure a proper base, or, in other words, a strong foundation, will prove to be 
firm and steady even in a strong wind. 

The methods of placing the verniers of a transit in such a position that they 
may be read without stepping aside while observing, is a feature in construction 
which has been pronounced objectionable, because the size of the plate level, 
which is at right angles to the line of collimation, and which is the more im- 
portant of the two, has to be reduced. The manner in which this can be over- 
come without reducing its length, or without placing it over one of the verniers 
(which must affect the degree of accuracy of the reading considerably), and the 
way in which this level may be set without allowing it to extend beyond the cir- 
cumference of the plate, will be explained on some other occasion. 

The Compass. — The compass should be made as large as possible, but with- 
out reducing the value of more important parts. It can often be noticed that an 
instrument with very large compass has the telescope standards fastened too far 
from the center, which reduces steadiness ; while others, of course still worse, 
have much spare room between standards and compass box. The point of the 
center-pin, as well as the upper ends of the needle, must lie in the same plane 
with the graduation, if the quivering motion which most sensitive needles possess, 
shall not be noticed on the reading points. As the accuracy depends principally 
on the pin and cap, these should consist of the best material, while the lift 
arrangement must be constructed in such a manner as to raise and lower the 
needle gently, in order to prevent the sudden jerking and falling, which is so 
often the cause for the rapid wearing out of the point and cap. 

Other Details. — It is an important feature of most all of the later instru- 
ments that the clamp by which the horizontal circle is held in position works 
toward the center on a collar, instead of being clamped on the circumference of 
the plate, and that all tangent screws are provided with opposing springs. 

It is also important that the telescope standards have bases large enough to 
secure proper connections with the plate. It is, furthermore, of great importance 
to insure steadiness that the lower parts containing fhe leveling screws be made 
out of one solid star-shaped casting, instead of the common round plates into 
which the nuts are simply stuck. There seems to be no other reason for making 
this latter style than to save a few dollars in labor. 

It goes without saying that all transit instruments should be provided with 
shifting centers. 

The Tripod. — The tripod legs must be light and strong, and of good hard 
wood, in order to secure steadiness, and should be fitted from the outside, so that 
any shrinkage of the wood may be drawn up by a nut at any time. In the older 
style, where the legs fit inside, this cannot be accomplished, and in that case it 
not only reduces the steadiness, but may also lead to serious accidents. The split 
or skeleton legs are best suited to come up to all the requirements of a good 
tripod. 

The Case. — The manner in which an instrument is packed in its case is by no 
means unimportant. A transit must stand upright, so that it may be taken out 
by holding the lower base-plates and leveling screws, and not the upper plates or 
the telescope axis. 



102 



MODERN SURVEYING INSTRUMENTS. 



The Finish. — The outer finish of an instrument, although having little to do 
with its accuracy, will always be found of some elegance in a first-class article. 
Unfortunately, most of the second-class possess a brilliant finish that only too 
often leads purchasers to overlook the more important parts. If engineers, when 
selecting instruments, would thoroughly test the finer qualities, and take into 
consideration the construction, they would not only be certain to get a more 
perfect article, but would induce makers to construct and build instruments in 
accordance with scientific principles. 

Discussion. 

By Mr. Luther Wagoner. 

The paper is a good practical resume of the principal points concerning the 
working qualities of a field instrument, and I presume it refers solely to the 
selection of a new article. 

My experience is that instruments do not often retain the good points shown 
in the shop after the ordinary usage and almost inevitable rough handling in the 
field and especially in transportation. 




These injuries are usually springing or bending of the centers and eccen- 
tricity; that is, the two axes are not coincident, and the latter condition is one 
common to nearly all instruments in a greater or less degree. I have seen it 
large enough to cause an error of three minutes in a right angle. 

As it may be necessary to try to do good work with such an instrument, 
I will explain my method of examining an instrument having two verniers. 

Set one vernier at zero and read the other, calling less than 180 degrees 
minus and more than 180 degrees plus; take such readings,, say, every 15 degrees 
on the circle and tabulate them properly. The mean of all the readings will be 



THE A. LIETZ COMPANY. IO3 

the angular difference of the verniers from 180 degrees ; subtract this mean 
quantity from each of the original readings (having due regard to the algebraic 
signs), and then use the resultant new column, as follows: 

With any convenient radius draw a circle on a cardboard and divide the 
circle into as many parts as there are observations, numbering the card like the 
instrument ; then using the circle as a base-line, plot the resultant new column, 
calling inside radical lines minus and outside radical lines plus, using any con- 
venient scale; join the points thus plotted, and cut out with a sharp knife the 
resultant figure, as shown in the accompanying engraving by shaded lines ; 
balance it over a knife-edge in two or more positions, and mark the center of 
gravity thus found. Replace the figure in the cardboard, and with the original 
radius and center of gravity as a new center draw a circle. (See figure.) The 
variations from this new circle are the residual errors due to graduation and 
observation. 

Unless an instrument was either very poor originally, or has been very 
roughly handled, these residuals should not exceed a few seconds 

The center of gravity found by the above method is the vernier-plate axis ; 
its distance from the original center is the amount of eccentricity measured by the 
scale used for plotting the figure, and a line drawn through the two axes gives its 
direction. 



No. 5. 

A SHORT AND PRACTICAL METHOD TO FIND THE 
LENGTH OF ONE MINUTE OF LONGITUDE IN 
ANY LATITUDE, BASED UPON CERTAIN 
DEVELOPMENTS OF THE TERRES- 
TRIAL SPHEROID. 



By OTTO VON GELDERN. 



For the determination of arcs of the Parallel and Meridional arcs, certain 
elements of the terrestrial spheroid have been used. 

Up to within the last ten or fifteen years, Bessel's determinations of the 
earth's magnitude were employed, which were : 

Equatorial Radius, a = 6,377,397 meters, 
Polar Radius, . b = 6,356,079 meters. 

Compression =^53 

Upon these elements the usual tables for the polyconic projection of maps 
were based, until those of Col. A. R. Clarke, R. E., were adopted, which furnish 
results more in harmony with recent geodetic measurements. Colonel Clarke's 
researches were published in his Comparison of the Standards of Length of 
England, France, Belgium, Prussia, Russia, India and Australia, made at the 
Ordnance Survey Office, Southampton, 1866. 

The U. S. Coast and Geodetic Survey has adopted the Clarke form, and 
published a long and carefully computed series of polyconic projection tables for 
it in 1884, which are still in use. (See Appendix No. 6, Report 1884.) 

Limiting the figure to that of an ellipsoid of revolution, Clarke's values are : 

a = 6,378,206 meters, 

exceeding Bessel's 809 m - 
b = 6,356,584 meters, 

exceeding Bessel's 505 m - 

Compression ^L 

It shows that this spheroid is somewhat larger than Bessel's and that the 
eccentricity is also greater. 

These elements have satisfied the conditions developed during scientific 
measurements of large areas, so that they may be safely adopted without fear of 
appreciable error. 

It is not the present purpose to enter into the subject mathematically. 

If the earth were a perfect sphere with a radius R, the expression for the 
value of one minute of longitude in any latitude would be 

, , 2 R n 
cos lat.-— — 

360 X 60 

Assuming R equal to the length of the equatorial radius, 6,378,206 meters, the 
constant 1855.3 is obtained for the second member. By this constant the cosine of 



THE A. LIETZ COMPANY. IC>5 

the latitude would have to be multiplied, in order to determine the length of one 
minute of longitude in meters. Or logarithmically expressed it is: 

log. cos lat. + 3.2684256. 

As we are dealing with a compression of nearly — however, it becomes 

necessary to take some recognition of this fact in the determination of distances 
on the parallel. For our present purpose it will answer if we find a method that 
shall furnish results approaching the truth within reasonably narrow limits, 
without considering exact mathematical formulae for obtaining very great pre- 
cision. 

After a careful study of this subject, based upon comparisons with very exact 
tabular values, the following method is proposed by the author, who has had 
occasion to make frequent use of it. 

Approximate Method. 

If the length of one minute of arc on the parallel be required, that shall not 
vary greatly from the correct value, observe the following rule : 

lo the logarithmic constant 3.2684256 add the logarithmic cosine of any 
given latitude less 5 minutes, and the result will be the length in meters of one 
minute of longitude in the given latitude. 

Example: — What is the length of one minute of longitude in latitude 37° 47'?' 

Log. constant .... 3.2684256 

Log. cosine of latitude 37° 42' 9.8982992 

(37° 47' — 05' = 37° 42') 3.1667248 

Answer, 1468.0 meters. 

(Correct within 0.2 m -) 

By this method results are obtained correct within 0. 3 m - from the equator up 
latitude 60° ; from 60° to 70" within 0. 5 m - ; beyond that limit the deviations from 
the true values grow more rapidly, yet even at 80° a minute of longitude thus 
obtained would have an excess of 1. 6 m - only. For all ordinary requirements,, 
therefore, the above rule will apply. 

A deduction of an even 5 minutes gives the best average results, and for that 
reason it has been adopted. If we want to be a little more precise about it, we 
may use 4 minutes from to latitude 25°, and from 65° upwards; 5 minutes from 
25° to 35°, and from 50° to 65° ; and 6 minutes from 35° to 50°. With this pre- 
caution the results will not vary more than 0. 2 m - for any case from the equator 
up to latitude 70°. 

If the distance is desired in feet instead of meters, multiply the result by 
3.28087, or use the logarithmic constant 3.7844146 instead of the one given above. 

A More Accurate Method. 

Where greater refinement is required, say that instead of one minute we 
should want the length of one degree of arc without appreciable error, the de- 
ductions from the latitude must be defined a little more closely still, if they shall 
furnish reliable results. 

By using the deductions given in minutes and seconds in the table below, for 
every 5° of latitude, results may be obtained that will be without appreciable 
deviation from the truth, even in the case of the length of one degree on a 
parallel. 



In latitude 


0° 


deduct 0' 0". 


In latitude 


45° 


deduct 


5' 50'. 


" " 


5° 


1' 00". 


" " 


50° 




t 


5' 40'. 


a a 


10° 


1' 50". 


a a 


55° 




t 


5' 30'. 


it a 


15° 


2' 40". 


u a 


60° 




' 


5' 00'. 


" " 


20° 


3' 50". 


a a 


65° 




' 


4' 30'. 


" " 


25° 


4' 30". 


a a 


70° 




' 


3' 50'. 


« a 


30° 


5' 00". 


a a 


75° 




* 


3' 00" 


a it 


35° 


5' 30". 


a a 


80° 


" 


2' 00'. 


a it 


40° 


5' 40'. 













106 MODERN SURVEYING INSTRUMENTS. 

Any intermediate value may be interpolated. 

Referring again to the previous example, let us find the value of one minute 
of longitude in latitude 37° 47' by this method. 

By consulting our table we find that for 37° 47' we must deduct 5' 35", 
leaving 37° 41' 25". Then write: 

Log. constant, 3.2684256 

Log. cosine of latitude 37° 41' 25", 9.8983724 



3.16677980 
Answer, ......... 1468.2 meters. 

(Which is correct to the nearest tenth.) 

If the length of a degree is wanted, multiply the result by 60, or use the 
constant 5.0465769 instead of the one above given. 

Example : — What is the length of one degree of longitude in latitude 17° ? 

Log. constant, . . . 5.0465769 

Log. cosine 16° 56' 45", 9.9807216 

(17° — 3' 15") 5.0272985 

Answer, ......... 106,487 meters. 

(Which is correct to the nearest meter.) 

Again, for latitude 74° ? 

Log. constant. . . . 5.0465769 
Log. cosine 73° 56' 50", 9.4417308 



4.4883077 
Answer, . '. . . . . . . . 30,782 meters. 

(Correct within 1 meter.) 

These results are readily reduced to either nautical or statute miles, by 
dividing by 1853.248 (log. 3.2679335) in the former, and by 1609.33 (log. 
3.2066449) in the latter case. The logarithmic constant may be changed to suit 
these measures. 

The Nautical Mile. 

The length of a nautical mile has been adopted at 1853.248 meters, or 6080.27 
feet. It will be noticed that this is 2.1 meters less than the length of one minute 
of longitude at the equator, which is ordinarily assumed as that which defines 
the nautical mile. The fact is that this unit of measure has been arbitrarily 
based, and that it varies as the data from which the deductions are made. In 
order to establish uniformity for all time, the nautical mile is now defined as the 
length of one minute of a great circle of a sphere that shall have the same 
superficial area as the terrestrial spheroid. This basis was adopted by the United 
States Coast and Geodetic Survey, and computed from Clarke's elements. 



Length of One Minute of Latitude in Different Latitudes. 

At the Equator, . . .• 1842.8 meters At 50°, 1853.8 meters 

" 10°, 1843.4 " " 60°, 1856.9 " 

" 20°, 1845.0 " " 70° 1859.4 " 

" 30°, 1847.5 " " 80°, 1861.1 " 

" 40°, 1850.5 " " 90°, 1861.7 " 



No. 6. 



THE SAEGMULLER SOLAR ATTACHMENT* AND VER- 
TICAL SIGHTING TELESCOPE. 

(Patented May 3, 1881.) 

How to Adust and Use It, with Refraction Tables. 



This attachment to the regular engineer's transit, by means of which the 
astronomical meridian may be obtained in a few minutes with an accuracy 
scarcely thought to be possible, has met with such success that it bids fair to 
supersede all other methods for the determination of the meridian by means of 
engineering instruments. 

The transit has come to be the universal instrument for the engineer, and 
will be for the surveyor sooner or later, and the attachment of the solar apparatus 
to the transit has thus become a necessity. 

Since its first introduction this attachment has been greatly improved, and, 
as now made, is nearly perfect. 

Attached to any transit which possesses a telescope, level and a vertical circle, 
it will give the meridian within the nearest minute. By using instruments which 
have a finer graduated vertical circle and better levels than are usually found on 
transits, the meridian can be determined with greater accuracy still. 

Advantages of the "Saegmiiller Solar Attachment" Over the Old Form. 

First — It is more accurate. 

Second — It is simpler and easier of adjustment. 

Third — It can be used when the sun is partly obscured by clouds, when the 
ordinary "solar" fails altogether. 

Fourth — It can be used where the sun is quite close to the meridian. 
Fifth — The time can be obtained with it reliable to within a few seconds with 
perfect ease. 

Sixth — It can be used as a vertical sighting telescope. 

It is as superior to all forms hitherto used as the transit is to the ordinary 
compass, or as a telescope is to common sights. 

The sights of an ordinary solar compass consist merely of a small lens and a 
piece of silver with lines ruled on it placed in its focus. This is simply a very 
primitive telescope, since the exact coincidence of the sun's image with the lines 
has to be determined by the unaided eye, or at best with a simple magnifying 
glass. 

That far greater precision can be attained by means of a suitable telescope 
is obvious ; in fact, the power of the solar telescope is in keeping with the transit 
telescope, as it should be. 

A glance at the illustration will show that the "Saegmuller Solar Attach- 
ment" is far simpler than the ordinary form. By raising or depressing, it can be 
set to north or south declination. To effect this with the ordinary solar compass 
two sets of primitive telescopes — one answering for north, the other for south 
declination— rare required, which are difficult to adjust. 

The addition of the level on the solar telescope dispenses with the declination 



* Reprinted by permission, and revised for this Manual. 



108 MODERN SURVEYING INSTRUMENTS. 

arc altogether, the arc or circle on the transit also serving for that purpose in 
conjunction with it. 

The "Saegmuller Solar Attachment" is, in fact, the only one which should be 
used in connection with a transit instrument. It sokes the solar problem, as has 
been attested by leading astronomers and engineers who have used it. 

Professor J. B. Johnson, of Washington University, St. Louis, Mo., has 
given it a thorough test, and writes as follows : 

"In order to determine just what accuracy was possible with a Saegmuller 
Solar Attachment, I spent two days in making observations on a line whose 
azimuth had been determined by observations on two nights on Polaris at elon- 
gation, the instrument being reversed to eliminate errors of adjustment. Forty- 
five observations were made with the solar attachment on October 24, 1885, from 
9 to 10 a. m., and from 1 :30 to 4 p. m., and on November 7, forty-two observations 
between the same hours. 

"On the first day's work the latitude used was that obtained by an observation 
on the sun at its meridian passage, being 38° 39', and the mean azimuth was 20 
seconds in error. On the second day, the instrument having been more carefully 
adjusted, the latitude used was 38° 37', which was supposed to be about the true 
latitude of the point of observation, which was the corner of Park and Jefferson 
Avenues in this city. It was afterwards found that this latitude was 38 ci 37' 15", 
as referred to Washington University Observatory, so that when the mean 
azimuth of the line was corrected for this 15" error in latitude, it agreed exactly 
with the stellar azimuth of the line, which might have been 10" or 15" in error. 
On the first day all the readings were taken without a reading glass, there being 
four circle readings to each result. On the second day a glass was used. 

"On the first day the maximum error was 4 minutes, the average error was 
0.8 minute, and the 'probable error of a single observation' was also 0.8 minute. 
On the second day the maximum error was 2.7 minutes, the average error was 
1 minute, and the 'probable error of a single observation' was 0.86 minute. The 
time required for a single observation is from three to five minutes. 

"I believe this accuracy is attainable in actual practice, as no greater care 
was taken in the adjustment or handling of the instrument than should be exer- 
cised in the field. 

"The transit has come to be the universal instrument for the engineer, and 
should be for the surveyor ; so it is more desirable to have the solar apparatus 
attached to the transit than to have a separate instrument. The principal advan- 
tages of this attachment are : 

"1. Its simplicity. 

"2. Its accuracy of pointing, being furnished with a telescope which is 
accurately set on the sun's disk. 

"3. In its providing that all angles be set off on the vertical and horizontal 
limbs of the transit, thus eliminating the eccentricity and other inaccuracies 
usually found in attachment circles or arcs. 

"4. Its small cost. 

"It is also readily removed and replaced without affecting its adjustments, 
and is out of the way in handling and reversing the telescope. It may be attached 
to any transit." 



THE 



LIETZ COMPANY. 



109 




A. LlETZ CO 

Makers 
San Francisco 



SAEGMULLER SOLAR ATTACHMENT. 

This instrument may be had in ALUMINUM, which gives that lightness 
particularly desirable in an attachment of this character. 

The illustration represents the improved "Saegmuller Solar Attachment" as 
now made. It consists essentially of a small telescope and level, the telescope 
being mounted in standards, in which it can be elevated or depressed. The 
standard revolves around an axis, called the polar axis, which is fastened to the 
telescope axis of the transit instrument. The telescope, called the "Solar Tele- 
scope," can thus be moved in altitude and azimuth. Two pointers attached to 
the telescope to approximately set the instrument, are so adjusted that when the 
shadow of the one is thrown on the other the sun will appear in the field of view. 



Adjustment of the Apparatus. 

1. The transit must be in perfect adjustment, especially the levels on the 
telescope and the plates ; the cross-axis of the telescope should be exactly hori- 
zontal, and the index error of the vertical circle carefully determined. 

2. The polar axis must be at right-angles to the line of collimation and 
horizontal axis of main telescope. 

To effect this, level the instrument carefully and bring the bubble of each 
telescope level to the middle of its scale. Revolve the solar around its polar 
axis, and if the bubble remains central, the adjustment is complete. If not, correct 
half the movement by the adjusting screws at the base of the polar axis, and the 
other half by moving the solar telescope on its horizontal axis. 

3. The line of collimation of the solar telescope and the axis of its 
level must be parallel. 

To effect this, bring both telescopes in the same vertical plane and both 
bubbles to the middle of their scales. Observe a mark through the transit tele- 



110 MODERN SURVEYING INSTRUMENTS. 

scope, and note whether the solar telescope points to a mark above this, equal 
to the distance between the horizontal axes of the two telescopes. If it does not 
bisect this mark, move the cross-wires by means of the screws until it does. 
Generally the small level has no adjustments, and the parallelism is effected only 
by moving the cross-hairs. 

The adjustments of the transit and solar should be frequently examined, and 
kept as nearly perfect as possible. 

Directions for Using the Attachment. 

First. — Take the declination of the sun as given in the Nautical Almanac* for 
the given day, and correct it for refraction and hourly change. Incline the transit 
telescope until this amount is indicated by its vertical arc. If the declination of the 
sun is north, depress it ; if south, elevate it. Without disturbing the position of 
the transit telescope, bring the solar telescope into the vertical plane of the large 
telescope, and to a horizontal position by means of its level. The two telescopes 
will then form an angle which equals the amount of the declination, and the incli- 
nation of the solar telescope to its polar axis will be equal to the polar distance of 
the sun. 

Second. — Without disturbing the relative positions of the two telescopes, in- 
cline them and set the vernier to the colatitude of the place. 

By moving the transit and the "Solar Attachment" around their respective 
vertical axes, the image of the sun will be brought into the field of the solar tele- 
scope, and after accurately bisecting it, the transit telescope must be in the 
meridian, and the compass-needle indicates its deviation at that place. 

The vertical axis of the "Solar Attachment" will then point to the pole, the 
apparatus being in fact a small equatorial. 

Time and azimuth are calculated from an observed alti- 
tude of the sun by solving the spherical triangle formed by 
the sun, the pole, and the zenith of the place. The three sides, 
S P, P Z, Z S, complements respectively of the declination, 
latitude and altitude, are given, and we hence deduce S P Z, 
the hour angle, from apparent noon, and P Z S the azimuth of 
the sun. 

The "Solar Attachment" solves the same spherical triangle 
by construction, for the second process brings the vertical axis 
of the solar telescope to the required distance, Z P, from the 
zenith, while the first brings it to the required distance, S P, 
from the sun. 

Observation for Time. 

If the two telescopes, both being in position — one in the meridian, and the 
other pointing to the sun — are now turned on their horizontal axes, the vertical 
remaining undisturbed, until each is level, the angle between their directions 
(found by sighting on a distant object) is S P Z, the time from apparent noon. 

This gives an easy observation for correction of time-piece, reliable to within 
a few seconds. 

To Obtain the Latitude with the "Saegmuller Solar Attachment." 

Level the transit carefully and point the telescope toward the south, and ele- 
vate or depress the object end, according as the declination of the sun is south 
or north, an amount equal to the declination. 

Bring the solar telescope into the vertical plane of the main telescope, level 
it carefully and clamp it. With the solar telescope observe the sun a few minutes 
before its culmination; bring its image between the two horizontal wires by 
moving the transit telescope in altitude and azimuth, and keep it so by the slow- 
motion screws until the sun ceases to rise. Then take the reading of the verti- 
cal arc, correct for refraction due to altitude by the table below. Subtract the 
result from 90°, and the remainder is the latitude sought. 




A Nautical Almanac must be a part of the engineer's field outfit. 



THE A. LIETZ COMPANY. 



Ill 



Mean Refraction. 
Barometer 30 inches, Fahrenheit thermometer 50 degrees 



Altitude. 


Refraction. 


Altitude. 


Refraction 


10' 


5' 10' 


20' 


2' 39' 


11 


4 51 


25 


2 04 


12 


4 27 


30 


1 41 


13 


4 07 


35 


1 23 


14 


3 49 


40 


1 09 


15 


3 34 


45 


58 


16 


3 20 


50 


49 


17 


3 08 


60 


34 


18 


2 57 


70 


21 


19 


2 48 


SO 


10 



The following table, computed by Prof. Johnson, C. E., Washington Univer- 
sity, St. Louis, will be found of considerable value in solar compass work : 

''This table is valuable in indicating the errors to which the work is liable at 
different hours of the day and for different latitudes, as well as serving to cor- 
rect the observed bearings of lines when it afterwards appears that a wrong lati- 
tude or declination has been used. Thus on the first day's observations I used a 
latitude in the forenoon of 38° 37', but when I came to make the meridian obser- 
vation for latitude I found the instrument gave 38° 39'. This was the latitude 
that should have been used, so I corrected the morning's observations for two 
minutes' error in latitude by this table. 

Errors in Azimuth (by Solar Compass) for 1 Minute Error in Declination or Latitude. 



Hook. 


For 1 Min. Error in Declina- 
tion. 


For 1 Mix. Error ix Lati- 
tude. 




Lat. 30° 


Lat. 40° 


Lat. 50° 


Lat. 30° 


Lat. 40° 


Lat. 50° 


11:30 A. M... \ 
12:30 P. M... j 

11 A. M \ 

1 P. M.. j 

10 A. M 1 

2 P. M J 

9 A. M \ 

3 P. M J 

S A. M \ 

4 P . M j 

7 A . M 1 

5 P . M j 

G A.M \ 

G P . M J 


MIN. 

8.85 
4 46 
2.31 
1 63 
1 34 
1.20 
1.15 


MIX. 

10.00 
5.05 
2.61 
1 85 
1.51 
1.35 
1.30 


MIX. 

12.90 
6.01 
3.11 
2.20 
1.80 
1.61 
1.56 


MIX. 

8.77 
4.33 
2.00 
1.15 
0.67 
0.31 
0.00 


MIX. 

9.92 
4.87 
2.26 
1.30 
0.75 
0.35 
0.00 


MIN. 

11.80 
5.80 
2.70 
1.56 
0.90 
0.37 
0.00 



Note. — Azimuths observed with erroneous declination, or co-latitude may be corrected by 
means of this table by observing that for the line of collimation set too high, the azimuth of 
any line from the south point in the direction of S. W. N. E. is found too small in the fore- 
noon and too large in the afternoon by the tabular amounts for each minute of error in the 
altitude of the line of sight. The reverse is true for the line set too low. 



112 MODERN SURVEYING INSTRUMENTS. 

"It is evident that if the instrument is out of adjustment the latitude found 
by a meridian observation will be in error; but if this observed latitude be used 
in setting off the colatitude, the instrumental error is eliminated. Therefore, 
always use for the colatitude that given by the instrument itself in a meridian 
observation." 

Correction for Refraction. 

This correction is applied to the declination of the sun, and is equal to the 
refraction-correction of the sun's observed altitude multiplied by the cosine of 
the angle which the sun makes between the declination-circle and the vertical. 

In order to reduce the refraction correction to the simplest possible form, we 
have added a table showing the refraction for every day of the year, at different 
hours, for latitude 40°, in 5-day periods. 

The Preparation of the Declination Settings for a Day's Work. 

The Solar Ephemeris gives the declination of the sun for the given day, for 
Greenwich mean noon. Since all points in America are west of Greenwich, by 5, 
6, 7 or 8 hours, the declination found in the ephemeris is the declination at the 
given place at 7, 6, 5 or 4 o'clock a. m., of the same date, according as the place 
lies in the "Eastern," "Central," "Mountain" or "Western Time" belts respectively. 

The appended, termed "Refraction Correction," gives the correction to be 
made to the declination, for refraction, for any point whose latitude is 40°. If 
the latitude is more or less than 40°, these corrections are to be multiplied by the 
corresponding coefficients given in the table of "Latitude Coefficients."* Thus the 
refraction corrections in latitude 30° are 65 hundredths, and those of 50°, 142 
hundredths of the corresponding ones in latitude 40°. There is a slight error in 
the use of these latitude coefficients, but the maximum error will not amount to 
over 15", except when the sun is very near the horizon, and then any refraction 
becomes very uncertain. All refraction tables are made out for the mean, or 
average refraction, whereas the actual refraction at any particular time and place 
may not be more than one-half, or as much as twice the mean refraction, with 
small altitudes. The errors made in the use of these latitude coefficients are, 
therefore, very small as compared with the errors resulting from the use of the 
mean, rather than unknown actual refraction which affects any given observation 

Example I. 

Let it be required to prepare a table of declinations for a point whose lati- 
tude is 38° 30', and which lies in the "Central Time" belt, for April 5, 1890. 

Since the time is 6 hours earlier than that at Greenwich, the declination given 
in the ephemeris of the Nautical Almanac is the declination here at 6 a. m. of 
same date. This is found to be -j- 6° 9' 57". To this must be added the hourly 
change, which is also plus, and equal to 56". 83. The latitude coefficient is 0.94, 
and the refraction corrections which must be multiplied by 0.94 are found in our 
table for April 5th, as follows : 

1st hour 0' 39" X 0.94 = 0' 37" 

2d " 0' 44" X 0.94 = 0' 41" 

3d " 0' 54" x 0.94 = 0' 51" 

4th " V 14" X 0.94 = 1' 10" 

5th " 2' 08" X 0.94 = 2' 00" 

The same corrections apply to the 4th, 5th, 6th, 7th, and 8th of April, but 
they are strictly exact for the middle day of the 5-day period corresponding to 
that set of hourly corrections only. For the extreme days of any such period 
an interpolation can be made between the adjacent hourly corrections, if desired. 

* This table just precedes the "Refraction Correction" table, see following pages. 



THE A. LIETZ COMPANY. 



JI 3 



The following table may now be made out : 

Declinalion Settings for April 5, 1890, Lat. 38° 30', Central Time. 



Hour. 


Declination 


Ref, Cor. 


Setting. 


Hour. 
I 


Declination. 


Ref. Cor. 


Setting. 


7 


+6° 10' 54" 


-f2' 00" 


6° 12' 54' 


1 


6° 16' 35" 


+ 37" 


6° 17' 12* 


8 


6 11 51 


+1 io 


6 13 01 


2 


6 17 31 


+ 41 


6 18 12 


9 


6 12 47 


+ 51 


6 13 38 


3 


6 18 28 


+ 51 


6 19 19 


10 


6 13 44 


+ 41 


6 14 25 


4 


6 19 25 


4-1' 10" 


6 20 35 


11 


6 14 41 


-f 37 


6 15 18 


5 


6 20 22 


+2 00 


6 22 22 








Examp 


le II. 









Let it be required to prepare a declination table for a point in Lat. 45 c \ in the 
"Eastern Time" belt, for October 10, 1890. 

The time now is 5 hours earlier than that of Greenwich, hence the declination 
given in the ephemeris for Greenwich mean noon is the declination at our point 
at 7 a. m. The declination found is — 6° 43', 56", and the hourly change is 
— 56". 87. Our latitude coefficient is 1.20. 

The table then becomes : 



Declination Settings for October 10, 1890, Lat. ^5°, Eastern Time. 



Hour 


Declination. 


Ref. Cor. 


Settings. 


i 

Hour 
1 


Declination. 


Ref Cor. 


Settings 


7 


—6° 43' 56" 


+ 5' 35" 


—6° 38' 21" 


-6° 49' 37" 


4- 1' 16' 


-6'48' 21" 


8 


-6 44 53 


+ 2 31 


—6 42 22 


2 


-6 50 34 


4- 1 24 


-6 49 10 


9 


—6 45 50 


+ 1 44 


—6 44 06 


3 


-6 51 31 


4- 1 44 


-6 49 47 


10 


—6 46 47 


-f 1 24 


—6 45 23 


4 


—6 52 28 


+ 2 31 


-6 49 57 


11 


—6 47 44 


4- 1 16 


—6 46 28 


5 


—6 53 25 


4- 5 35 


-6 47 50 



If the date be between June 20, and September 20, the declination is positive, 
and the hourly change negative ; while, if it be between December 20, and March 
20, the declination is negative and the hourly change positive. The refraction 
correction is always positive — that is, always increases numerically the north 
declinations, and diminishes numerically the south declinations. 

By using standard time instead of local time, a slight error is made, but the 
maximum value of this error is found at those points where the standard time 
differs from the local time by one-half hour, and in the spring and fall when the 
declination is changing rapidly. The greatest error, then, is, less than 30", and 
this is smaller than can be set off on the vertical circle or declination arc. Even 
this error can be avoided by using the true difference of time from Greenwich 
in place of the standard meridian time. 



The Saegmuller Solar Attachment When Used as a Vertical Sighting 

Telescope. 

Although this attachment is familiar to every engineer, it is only quite 
recently that it- has been recognized as the best Vertical Sighting Telescope which 
can easily be attached to the ordinary transit, and which will give accurate results. 

It is readily seen that the construction of the attachment allows the small 



114 



MODERN SURVEYING INSTRUMENTS. 



telescope to be placed in a vertical position, and when so placed, as represented 
in our illustrations of transits with solar attachments, it fulfills every requirement 
of an instrument designed for vertical as well as oblique sighting in mining work. 

In order to use the solar for this purpose, proceed as follows : 

See that the transit is in perfect adjustment. Point both telescopes horizon- 
tal and see that the Solar points as much above the transit telescope as equals 
the distance between their axes. When this is the case the lines of collimation 
of both telescopes are parallel. Now turn the transit telescope 90°, as shown by 
the vertical circle, taking care not to disturb the relative position of the solar tele- 
scope and that of the transit, and both will point vertically downwards. 

As the standards of the Solar are high enough to allow the small telescope to 
clear the plates, it is evident that the solar telescope now points accurately to the 
Nadir. 

The same modus operandi holds good when it is desired to obtain an oblique 
sight, as it is only necessary to set off the desired slope on the vertical circle, 
after having both telescopes parallel. 

For very accurate work it is desirable to make the observations in two posi- 
tions by reversal. By taking the mean of the two sets of observations, instru- 
mental errors are eliminated. 

In order to make the Saegmuller Solar Attachment as efficient as possible 
for the above purpose, the size of the telescope has been increased, giving it 
ample power to locate a point with great precision. 

TABLE OF LATITUDE COEFFICIENTS, 

To be Used in Connection with the Refraction Correction Tables for 
Latitude 4O i (See the following pages.) 



La?. 


COEFF. 


Lat. 


COEFF. 


Lat. 


COEFF. 


15° 


.30 


31° 


.68 


47° 


1 29 




16 


.32 


32 


.71 


48 


1.33 




17 


.34 


33 


.75 


49 


1.38 




18 


.36 


34 


.78 


50 


1.42 




19 


.3S 


35 


.82 


51 


1.47 




20 


.40 


36 


.85 


52 


1.53* 




21 


.42 


37 


.89 


53 


1.58 




22 


.44 


38 


.92 


54 


1.64 




23 


.46 


39 


.96 


55 


1.70 




24 


.48 


40 


1.00 


56 


1.76 




25 


.50 


41 


1.04 


57 


1.82 




26 


.53 


42 


1.0S 


58 


1.88 




27 


.56 


43 


1.12 


59 


1.94 




28 


.59 


44 


1.16 


60 


2.00 




29 


.62 


45 


1.20 








30 


| .65 


46 


1.24 









THE A. LIETZ COMPANY. 



"5 



REFRACTION CORRECTION*. 

Latitude 40°. 



Jan. 



10 

11 

12 
13 



15 
16 
17 
18 

19 

20 
21 
22 
23 

24 
25 
26 

27 
28 

29 
30 
31 



Refraction 




Refraction 




Refraction 




Correction 


Feb. 


Correction 


Mar. 


Correction 


Apr. 


Lat. 40 deg. 




Lat. 40 deg. 




Lat. 40 deg. 





h. ' " 








h. ' " 


1 1.58 


1 




1 


1 1.03 


1 


2 2.16 


2. 




2 


2 1.10 


2 


3 3.04 




h. ' " 


3 1.27 


3 


4 6.23 


3 


1 1.26 


3 


4 2.06 






4 
5 
6 


2 1.37 


4 


5 4.39 


4 
5 
6 


1 1.54 

2 2.11 


3 2.04 


5 


1 0.59 


7 


4 3.21 


6 


2 1.06 


7 


3 2.59 






7 


3 1.21 


8 


4 6.01 


8 


1 1.21 


8 


4 1.56 




1 1.51 


9 
10 
11 


2 1.31 

3 1.56 


9 
10 


5 4.04 
1 0.55 


9 
10 
11 


2 2.07 


12 


4 3.04 


11 


2 1.02 


12 


3 2.51 






12 


3 1.15 


13 


4 5.40 


13 


1 1.16 


13 


4 1.47 






14 


2 1.25 


14 


5 3.34 


14 


1 1.46 


15 


3 1.48 






15 


16 


4 2.47 


15 


1 0.52 


16 


2 2.01 


17 


5 8.39 


16 


2 0.58 


J7 


3 2.40 






17 


3 1.10 


18 


4 5.00 


18 


1 1.12 


18 


4 1.39 






19 


2 1.20 


19 


5 3.08 


19 


1 1.42 


20 


3 1.40 






20 


21 


4 2.31 


20 


1 0.48 


21 


2 1.56 


22 


5 6.49 


21 


2 0.54 


22 


3 2.31 






22 


3 1.05 


23 


4 4.35 


23 


1 1.07 


23 


4 1.32 






24 


2 1.15 


24 


5 2.51 


24 


1 1.37 


25 


3 1.33 






25 


2 1.50 


26 


4 2.18 


25 


1 0.45 


26 


27 


> 5.29 


26 


2 0.50 


27 


3 2.22 






27 


3 1.01 


28 


4 4.07 


28 




28 


4 1.25 






29 




29 


5 2.34 


29 


1 1.32 










30 


2 1.44 






30 


1 42 




3 2.13 






31 


2 0.47 




4 3.41 













Refraction 
Correction 
Lat. 40 deg. 



h. ' " 

3 0.57 

4 1.19 

5 2.18 

1 0.39 

2 0.44 

3 0.54 

4 1.14 

5 2.08 

1 0.36 

2 0.41 

3 0.51 

4 1.10 

5 1.58 



0.34 
0.38 
0.48 
1.06 
1.49 



1 0.32 

2 0.36 

3 0.45 

4 1.02 

5 1.42 

1 0.30 

2 0.34 

3 0.42 

4 0.58 

5 1.36 

1 0.28 

2 0.32 



May. 



9 
10 
11 
12 
13 

14 

15 
16 
17 
18 

19 
20 

21 
22 

23 

24 

25 
26 

27 
28 

29 

30 

31 



Refraction 
Correction 
Lat. 40 deg. 



h. ' " 

1 0.28 

2 0.32 

3 0.39 

4 0.55 

5 1.30 

1 0.26 

2 0.30 

3 0.37 

4 0.53 

5 1.26 

1 0.25 

2 0.29 

3 0.36 

4 0.51 

5 1.22 

1 0.23 

2 0.27 

3 0.34 

4 0.49 

5 1.18 

1 0.22 

2 0.26 

3 0.33 

4 0.47 

5 1.15 

1 0.21 

2 0.25 

3 0.32 

4 0.46 

5 1.13 

1 0.20 

2 0.24 

3 0.31 

4 0.44 

5 1.11 



Refrac- 
tion Cor- 
rection 
Lat. 

; 40 dig. 



Jl.' • 

5 1.11 



1 0.19 

2 0.23 

3 0.30 

4 0.43 

5 1.10 

1 0.18 

2 0.22 

3 0.29 

4 0.43 

5 1.09 

0.18 

2 0.22 

3 0.29 

4 0.42 

5 1.08 

1 0.18 

2 0.22 

3 0.29 

4 0.42 

5 1.08 

1 0.18 

2 0.22 

3 0.29 

4 0.42 

5 1.08 

1 0.18 

2 0.22 

3 0.29 

4 0.43 



* These corrections are strictly correct for the middle day only of the five-day period, for the hours as sho>vn. 
In the case of extreme days of the period, an interpolation may be made. 



n6 



MODERN SURVEYING INSTRUMENTS. 



REFRACTION CORRECTION. 

Latitude. 40°. 






























Refrac- 




Refraction 




Refraction 




Refraction 




Refraction 




Refraction 




tion Cor- 


July 


Correction 


Aug. 


Correction 


Sept. 


Correction 


Oct. 


Correction 


Nov. 


Correction 


Dec. 


rection 




Lat. 40 deg. 




Lat. 40 deg. 




Lat. 40 deg. 




Lat. 40 deg. 




Lat. 40 deg. 




Lat. 
40 deg. 




h. ' " 








h. ' " 


h. 


, ,, 




h. 




h.' " 


1 


5 1.09 


1 




1 


1 0.39 


1 


1 


0.59 


1 


2 


1.37 


1 


1 1.54 


2 








2 


2 0.44 


2 


2 


1.06 


2 


3 


2.04 


2 


2 2 11 








h. ' " 


3 


3 0.54 


3 


3 


1.21 


3 


4 


3.21 


3 


3 2.59 


3 


1 0.19 


2 


1 0.26 


4 


4 1.14 


4 


4 


1.56 


4 


5 


13.57 


4 6 01 


4 


2 0.23 


3 


2 0.30 


5 


5 2.08 


5 


5 


4.04 








4 


5 


5 


3.0.30 


4 


3 0.37 












5 


1 


1.32 






6 


4 0.43 


5 


4 0.53 


6 


1 0.42 


6 


1 


1.03 


6 


2 


1.44 


5 


1 1.58 


7 


5 1.10 


6 


5 1.26 


7 


2 0.47 


7 


2 


1.10 


7 


3 


2.13 


6 


2 2.16 










8 


3 0.57 


8 


3 


1.27 


8 


4 


3.41 


7 


3 3.04 


8 


1 0.20 


7 


1 0.28 


9 


4 1.19 


9 


4 


2.06 


9 


5 




8 


4 6.23 


9 


2 0.24 


8 


2 0.32 


10 


5 2.18 


10 


5 


4.39 








9 


5 


10 


3 0.31 


9 


3 0.39 












10 


1 


1.37 






11 


4 0.44 


10 


4 0.55 


11 


1 0.45 


11 


1 


1.07 


11 


2 


1.50 


10 


1 2.00 


12 


5 1.11 


11 


5 1.30 


12 


2 0.50 


12 


2 


1.15 


12 


3 


2.22 


11 


2 2.19 










13 


3 1.01 


13 


3 


1.33 


13 


4 


4.07 


12 


3 3.09 


13 


1 0.21 


12 


1 0,30 


14 


4 1.25 


14 


4 


2.18 


14 


5 




13 


4 6.38 


14 


2 0.25 


13 


2 0.34 


15 


5 2.34 


15 


5 


5.39 








14 


5 


15 


3 0.32 


14 


3 0.42 












15 


1 


1.42 






16 


4 0.46 


15 


4 0.58 


16 


1 0.48 


16 


1 


1.12 


16 


2 


1.56 


15 


1 2.01 


17 


5 1.13 


16 


5 1.36 


17 


2 0.54 


17 


2 


1.20 


17 


3 


2.31 


16 


2 2.20 










18 


3 1.05 


18 


3 


1.40 


18 


4 


4.35 


17 


3 3.11 


'18 


1 0.22 


17 


1 0.32 


19 


4 1.32 


19 


4 


2.31 


19 


5 




18 


4 6.47 


19 


2 0.26 


18 


2 0.36 


20 


5 2.51 


20 


5 


6.29 








19 


5 


20 


3 0.33 


19 


3 0.45 












20 


1 


1.46 






21 


4 0.47 


20 


4 1.02 


21 


1 0.52 


21 


1 


1.16 


21 


2 


2.01 


20 


1 2.01 


22 


5 1.15 


21 


5 1.42 


22 


2 0.58 


22 


2 


1.25 


22 


3 


2.40 


21 


2 2.20 










23 


3 1 ■.. 10 


23 


3 


1.48 


23 


4 


4.59 


22 


3 3.11 


23 


1 0.23 


22 


1 0.34 


24 


4 1.39 


24 


4 


2.47 


24 


5 




23 


4 6.49 


24 


2 0.27 


23 


2 0.38 


25 


5 3.08 


25 


5 


8.39 








24 


5 


25 


3 0.34 


24 


3 0.48 












25 


1 


1.50 






26 


4 0.49 


25 


4 1.06 


26 


1 0.55 


26 


1 


1.21 


26 


2 


2.06 


25 


1 2.00 


27 


5 1.18 


26 


5 1.49 


27 


2 1.02 


27 


2 


1.31 


27 


3 


2.49 


26 


2 2.19 










28 


3 1.15 


28 


3 


1.56 


28 


4 


5.33 


27 


3 3.09 


28 


1 0.25 


2.7 


I 0.36 


29 


4 1.47 


29 


4 


3.04 


29 


5 




28 


4 6.43 


29 


2 0.29 


28 


2 0.41 


30 


5 3.34 


30 


5 


11.01 








29 


5 


3 0.36 


29 


3 0.51 












30 










30 


4 0.51 


30 


4 1.10 








1 


1.26 








30 




31 


5 1.22 


31 


5 1.58 






31 












31 





No. 7. 

THE CYCLOTOMIC TRANSIT. 

By OTTO VON GELDERN. 



The Principle of the Instrument. 

The evolution of this instrument is clue to a constant tendency to create a 
transit with one spindle, i. e., having but one central cone turning within the level- 
ing head, that shall, at the same time, sacrifice none of the advantages that the 
so-called compound center possesses. 

It goes without saying that the principal advantage of the double spindle lies 
in the fact that, no matter in what direction the telescope may be pointed, the 
operator is enabled to make any azimuth of his graduated plate agree therewith. 
How this may be done without giving the lower plate an independent motion 
around the vertical axis of the instrument, is the problem to be solved. 

The lower plate is the important member that carries the graduated azimuth 
circle, and if it be made a part of the rigid substructure — of the leveling-head and 
base-plate — the control of it in reference to known azimuths is apparently lost. 
If we were enabled, however, to shift the figure-series — the nomenclature of the 
circle — at will, so as to make any one of the graduation lines the zero, the advan- 
tage lost by having a rigid lower plate would be regained. 

The novelty of the new transit lies in a floating exterior ring, placed around 
the periphery of the lower plate, upon which the figures from to 360 are engraved. 
These figures are then no longer a fixed part of the circle, but possess that inde- 
pendent rotation which the lower plate had in the case of the double spindle. 
Instead of turning the whole plate around its vertical axis, we turn a narrow 
metal band around the stationary plate, which is the same thing. 

As this band appears to be sliced from the plate, the name Cyclotome has 
been applied to it, from kvkXo^ ring or circle, and teulvelv, to cut, that is, a 
ring cut or severed as from a disk. 

Since the object of the ring is merely to designate the graduated lines upon 
the plate by corresponding figures, absolute concentricity of the cyclotome is not 
a matter of importance. 

The Construction. 

Attention is drawn to the illustrations herewith, figure 1 showing a vertical 
section through the plates, and figures 2 and 3 a top and bottom view respectively 
of the upper plate. In the vertical section the arrangement of the principal parts 
may be readily understood. 

The lower plate and the leveling-head become one member, which is mounted 
upon the base-plate in the ordinary manner. The cyclotome C is fitted exteriorly 
around the plate, its top resting upon the graduation, of which it is a part. 

The upper plate revolves upon the lower by means of its long and stout spin- 
dle, within the socket of the leveling-head. It carries the vernier V , visible 
through an opening in the plate, which also exposes a part of the graduated lower 
plate and a part of the cyclotome. The horizontal motion of the instrument is 
arrested by the clamp and collar, and the position adjusted by a tangent screw, as 
common to all transits. 

Compass box and telescope are mounted on the top of the plate, as usual. 

The flange forming the top of the lower plate is graduated into 720 even 
spaces of half-degree divisions. The vernier moves along the inner rim of this 
graduation, and is held whenever the line of collimation (the telescope) has the 



MODERN SURVEYING INSTRUMENTS 




CycZoioTrte C 



U O.-r.G 



Fig. 



Section thmu&h Mate* 

an One X • Center - Y, 
„,//? s/c/e v/en or Te/escope 



A. LJETZ CO. 



Seen, *™?%*-°> *** 



All risrhts reserved 



THE A. LIETZ COMPANY. 



119 




._y 



$&&%»"* 



r<5Lr/cLf/0/7 



Fig. 2. 

7b/o l//ew of* (//?/?e/~ /-V&fe 




Fig. 3. 



A. LIETZ CO 

San Francisco, Cal. 

April 1895^ 



All rights reserved 



120 MODERN SURVEYING INSTRUMENTS. 

desired direction. In order to effect a coincidence between the vernier's zero and 
the nearest half-degree division , the entire vernier may be shifted inde- 
pendently to the right or left by means of the screw A, shown in the illustrations, 
and in the manner presently to be explained. 

And having thusly determined upon and indicated one of the 720 lines to be 
the initial or starter, it would be necessary only to bring the zero of the cyclotome 
— or any other reading for that matter — to match this line. 

In the simpler form of the new transit, the exterior ring or cyclotome is 
revoluble by hand around the periphery of the plate, and the required azimuth 
is thus readily set off. In the improved form, as shown by the illustrations, the 
ring is encased, and so arranged that the upper plate in its rotation may or may 
not carry the cyclotome with it. It is picked up and revolved together with the 
telescope, or left at rest upon the lower plate in any desired position. It is 
within the power of the operator to manipulate this at will, and there are two 
means of doing so, as will be noted further on. 

As it is generally required to place the zero upon the azimuth from which 
observations are started, an automatic catch L (see figure 3), having a small pro- 
jecting pin n, is so arranged that whenever it is desired to make the cyclotome 
travel together with the upper plate, the pin n must be made to drop into a hole 
provided for it in the "cyclotome; the moment this takes place, the two (plate 
and cyclotome) are connected, and — this is a peculiar feature of the device — 
in such a position that the zero of the vernier V , and the zero of the cyclotome 
C are brought together, separated, of course, by the intervening graduated flange 
of the lower plate. If the vernier be now revolved with the upper plate, the 
figure-system will travel with it, their respective zeros coinciding. 

The bottom of the upper plate, figure 3, illustrates the mechanism with which 
all this is accomplished. U is a guide, fastened to the plate, for the arc W, carry- 
ing the vernier V. A strong spring vS presses the arc against the slide T, the 
position of the whole being regulated by the exterior screw A, which allows the 
adjustment of the vernier already referred to. The catch L is poised in T. The 
screw B raises or lowers the catch, so that with it we may throw the cyclotome 
either in or out. A small spring under the catch L admits of this. The mechan- 
ism is so simple that it needs no further description. 

With this device there is no difficulty in placing the zero of the horizontal 
circle so as to correspond with any pointing of the telescope. 

Use in the Field. 

The field manipulation is reduced to a minimum. 

Having set the instrument over a point (1) in the usual manner, it is desired 
to direct the telescope to another point (2), and to make the zero of the hori- 
zontal graduation correspond with this azimuth. The main clamp being loose, 
the first operation is to turn the screw B so that the catch L is depressed ; the 
upper plate is then turned, until a click indicates that the little pin n has caught 
the cyclotome and is carrying it along, with the zero in position, as explained. 
The operation is automatic to this extent, that the manipulator need not watch his 
plate to set the zeros. He will now direct the telescope to point (2), clamp the 
plate, and bisect the object with the tangent screw. His attention is thereupon 
directed to the vernier, for it is essential that its zero should correspond exactly 
with a line of the fixed graduation. He turns the screw A to the right, or left, 
shifting the vernier sufficiently to accomplish this. The cyclotome travels with 
the vernier, so that he does not need to watch it. The instrument is now oriented, 
the vernier indicating the starting azimuth, and measurements to other points may 
begin. Before commencing, however, the screw B is turned so as to release the 
catch and allow the cyclotome to remain in position. The instrument is now un- 
damped and ready for operation. Any subequent reading will indicate directly 
in degrees and minutes the deflection from the starting point. The whole opera- 
tion is simple and rapid, and will require less time than the setting of the com- 
pound-center instrument. 

If it be desired to set any other azimuth to a telescope pointing, recourse is 



THE A. LIETZ COMPANY. 121 

had to the clamp F (see top view of plate, figure 2), by which the cyclotome may 
be connected to the upper plate at any point. 

The operation is as follows : 

Set up instrument; drop catch L by a turn of screw B; revolve plate on 
center, click indicates that L has caught cyclotome C; point telescope, clamp 
plate and bisect object; shift zeros to the nearest graduation line by screw A; 
release cyclotome by screw B ; unclamp instrument and lay off the reading of the 
required azimuth to the nearest thirty minutes by means of the clamp and tangent 
screws, and then to the minute with precision by means of the screw A ; now turn 
down the screw F, which catches the cyclotome ; unclamp instrument, revolve 
on center, direct telescope to original object, clamp and bisect. The reading of the 
vernier will now indicate the azimuth wanted. Release the screw F and the 
cyclotome will remain in the position into which it has been brought. 

The reason wrry the reading is laid off to the nearest thirty-minute mark only, 
and then adjusted to precise reading by shifting the vernier, becomes obvious, 
if we remember that it is always necessary to match the graduation lines of the 
plate with those of the cyclotome, and that any setting disturbing their coincidence 
(readings from V to 29' and 31' to 59') will have to be corrected by a vernier 
displacement. 

This operation is rapid, although perhaps a trifle slower than the manipula- 
tion with the hand cyclotome, mentioned above, in which case the telescope is 
directed, plate clamped, object bisected, vernier zero brought to a line, cyclotome 
turned by hand to read within the nearest half degree of the line, after which 
the vernier is adjusted to the exact reading. 

The principle remains the same in either method, the only difference being 
that in the case of the hand cyclotome one is able to set it irrespective of the 
motions of the upper plate. 

After these explanations it becomes very obvious that there are no advan- 
tages that the double spindle system can claim over the cyclotomic system in the 
ready manipulation of the horizontal arc. 

Angular Repetition. 

While the reiteration of an angle, resorted to in geodetic measurements, to 
obtain the value of an arc with its probable error to the fraction of a second, is 
not possible with the cyclotomic transit, because the main graduation is fixed 
and cannot be turned in reference to the direction of the objects observed upon, 
it is perfectly feasible to take the same angle on different parts of the plate. 
Since there are two verniers, located 180 degrees apart, two readings may also 
be had of each measurement and the mean taken. 

Unless a double spindle transit be of the very best workmanship, that is, a 
first-class and therefore a high-priced article, all the reiteration and repetition 
will fail to reach a better result than that attainable with a well-built cyclotomic 
instrument, which is made to read to half minutes directly, or to twenty seconds 
in the larger sizes; and anything within the limits of this accuracy is guaranteed 
by the maker. As the reiteration of an angle is uncalled for in any but the most 
refined measurements, the cyclotomic transit does not lack completenes.s for the 
want of this particular feature. 

Advantages of the Cyclotomic Transit. 

The main feature is its single spindle. Its adoption obviates the necessity of 
the lower clamp and tangent screws, and simplifies this part of the transit very 
much. It affords an opportunity to bring the plates closer to the leveling-head, 
thereby lowering the center of gravity of the instrument. It sits directly, upon the 
rigid substructure, fitted into it by a thick metal axis and must therefore be very 
steady. The main graduation, the most vital part of the transit, is fixed for all 
time. Once properly centered, the chances for eccentricity are reduced to a 
minimum. The instrument possesses a comparing vernier, opposite the reading 
vernier (see figure 2), which shows through a circular opening in the plate. By 
means of the two, used in conjunction, the plate eccentricity may be accurately 
determined. 



122 MODERN SURVEYING INSTRUMENTS. 

What is justly claimed for this instrument as more advantageous than the 
compound-center transit is included in the following" : 

Greater simplicity ; reduction of parts and reduction of weight, with greater 
steadiness for instruments of the same size ; greater solidity of the axis, and 
therefore greater rigidity, and the least liability to serious injury through acci- 
dent; simple mechanism enabling a more rapid setting of the plates to the zero 
azimuth. 

In its optical appointments and constructive details, the instrument is up to 
the standard of a first-class modern transit and surveying instrument; it is a 
tachymeter, and fitted for any possible expediency of modern engineering. 

It has not been the object to replace the compound-center instrument with a 
cheap and inferior substitute, but rather to simplify the required parts and to 
improve, if possible, the stability and concentricity, without losing those features 
that have thus far made the double-center instrument the preferred one for 
meeting the manifold demands made by the profession upon a universal measur- 
ing tool. 

The Manufacture. 

The instrument in its present shape was designed in detail by Mr. Adolph 
Lietz, the original suggestion having been made to him by Mr. Luther Wagoner, 
civil engineer, of San Francisco, who had conceived the application of the float- 
ing ring or cyclotome. 

All rights have been legally secured by the designer, who is also the manu- 
facturer. 

The instrument is made in San Francisco, in different styles and sizes. In 
their main and essential parts all styles are alike, but they may vary a little in 
the arrangement of minor detail. In appearance the instrument does not differ 
from any standard type, except that the bulky apparatus of clamp, collar, tongue, 
spring case and tangent screw below the plates is missing, and that the plates 
sit a little closer to the base. 

The cyclotomic transit is particularly adapted to aluminum construction, by 
placing a light superstructure upon a firm and solid base. This will insure very 
great steadiness even in a strong wind. 

Remarks. 

It is very probable that the instrument will work itself into the favor of the 
profession, for while it has been much simplified, nothing has been sacrificed. 

The principle here made use of may be extended with advantage to many 
forms of arc-measuring apparatus, and will undoubtedly find a much wider 
application in time. Although extremely simple and readily understood by any- 
one, it will require a little field practice to make the engineer an expert in the 
use of the cyclotome, which, like the slide-rule, will be appreciated all the more 
the longer it is used and its advantages become apparent. 

Prices upon application. 



REVISED EDITION OF 

PART II 



ILLUSTRATED CATALOGUE AND PRICE LIST 

OF 

Modern Engineers' 
and Surveyors' Instruments 

Guaranteed in Every Detail 



THE A. LIETZ COMPANY 

Manufacturers of Scientific Instruments 

632-34 COMMERCIAL STREET 

SAN FRANCISCO 

CALIFORNIA 



INTRODUCTION TO PART II. 



The following illustrations show the principal articles manu- 
factured by this Company, being in the case of this catalogue 
almost exclusively confined to instruments required by the civil, 
mining, irrigation, hydraulic and military engineer, for making 
accurate measurements and surveys for any purpose whatever. 

Of the surveying instruments each illustration, or plate, is 
complete within itself. Every part is carefully noted upon the 
back, together with the price, and a general description in a con- 
densed form. The additional accessories that may be had in each 
instance, are also enumerated and their prices given. It is well, 
however, that the engineer who is looking for an article, should 
consult the preceding part of this Manual, wherein every detail 
is carefully described and extensively discussed. If pains are 
taken to look this over, the reader will obtain all the information 
that could possibly be given him in the shop. 

Every article has been numbered, and by these numbers our 
customers may order, without going into a minute description of 
the articles wanted. For example : 

"Send me transit No. 4 (1908), with the following extras " 

is all that is required to designate to us exactly what is desired by 
our patron. 

In ordering please mention the issue of the catalogue, as the 
numbers of preceding issues necessarily conflict. 

See also Telegraph Code in front of book. 

With the detailed information on its reverse side, every plate 
becomes a complete price list of the particular instrument illus- 
trated. Every effort has been made to make this part of the book 
as intelligible as possible, without the necessity of searching over 
numerous pages to gather information. 

Although we shall make any instrument of precision called for, 
we desire to state clearly that we have made, a particular specialty 
of engineers' and surveyors' instruments, because there is for them 
alone a demand at the present time, and for this reason our shop 
facilities have been especially designed and improved for the manu- 
facture of these articles. 

If instruments for a more scientific purpose are wanted, for 



THE A. LIETZ COMPANY. 1 25 

astronomical or geodetic work, for instance, we can either make 
them on a special order, or we can import them for our customer, 
having made arrangements in Europe, which enables us to sell 
such instruments as cheaply as any one in the United States. For 
institutions of learning we import without payment of duty. 

In all our manufacture the prices have been marked com- 
mensurate with the quality of the work, and no deductions can be 
made from our price list, which agrees in all its quotations with 
those of our best Eastern firms. 

We furnish a first-class article at a fair price, and all goods 
stand upon their individual merit. It has been our object to create 
the best that the instrument maker's art can make or devise, and 
with the records of the past decades before us we feel that we have 
been successful in every way. 

A. LIETZ COMPANY. 



ENGINEERS' AND SURVEYORS' TRANSITS. 

(Double Spindle Repeating.) 
Nos. i to 4. 

These are elegant instruments, absolutely accurate in all work- 
ing parts, designed for land surveying and engineering work of a 
high character. 

The general dimensions are given on the back of each illus- 
tration, as well as the price, and the extras that may be had upon 
application. By carefully inspecting the plates, the price list and 
the enumerated extras, the purchaser is enabled to choose the 
article and any desired accessory, and make an estimate of its cost. 

We make each style in hard aluminum, which increases the 
price 15 per cent. 

The horizontal circle is graduated to read to either 60, 30 or 
20 seconds, two double verniers being provided, placed so as to 
afford a reading without stepping aside. The vertical arc or circle 
is graduated to read to 60 or 30 seconds. Every instrument has 
long compound centers, shifting plates on tripod head, with new 
improved coupling. The telescope possesses definition, light and 
power in a high degree. It has Jena glass lenses, achromatic ob- 
jective and eye-piece. Erect vision. The telescope is reversible 
and evenly balanced, provided with slide protector, and screw 
motion for focusing cross-hairs. The standards are cloth-tinished. 
The case has leathern straps, rubber cushions, and contains all the 
usual accessories. For a minute description of every detail, see 
first part of the Manual. 



THE A. LIETZ COMPANY. 



127 




No. I. 
PLAIN TRANSIT. 

Price, $185.00. 

For details and extras see the following page. 



128 MODERN SURVEYING INSTRUMENTS. 



No. i. 
Dimensions and Weight. 

Horizontal Circle (measured to the edge of graduation) 6% r inches diam. 

Compass Needle A l / 2 " long 

Object Glass \y s " diam. 

Telescope 11 " long 

Magnifying power 24 

Weight of instrument 15 lbs. 

tripod Sy 2 " 

box .' 8 " 

Weight of this instrument if made of hard aluminum 7y^ " 

The price of this instrument as shown is $185 00 

And if made of hard aluminum, 15 per cent is added. 



The Extras, for which additional charge is made, are as follows: 

Solid Silver Graduations : 

On horizontal circle $10 00 

Verniers, reading to 30" 10 00 

20" 20 00 

Stadia hairs, fixed 3 00 

" adjustable 10 00 

Variation plate 10 00 

Arrangement for offsetting right angles 5 00 

Striding level to axis of telescope . 20 00 

Constructed with three leveling screws on base-plate, instead of four 10 00 

Three-leveling-screw shifting center 5 00 

Extra extension tripod in lieu of ordinary 5 00 

Protection bag 1 00 

Bottle of fine watch oil 25 

Note. — On all Lietz Transits the variation of the needle may be laid off to 
the minute, see page 34. 



THE A. LIETZ COMPANY. 



I29 




No. 2. 
TRANSIT, WITH LEVEL TO TELESCOPE. 

Price, $215.00. 

$£T For details and extras see the following page. 



130 MODERN SURVEYING INSTRUMENTS. 



No. 2. 
Dimensions and Weight. 

Horizontal Circle (measured to the edge of graduation) 6%. inches diam. 

Compass Needle A]/ 2 " long 

Object Glass iy 8 " diam. 

Telescope 11 " long 

Magnifying power .....: 24 

Weight of instrument 15 lbs. 

; " tripod S l / 2 " 

box 8 " 

Weight of this instrument if made of hard aluminum iy 2 " 

The price of this instrument as shown is $215 00 

And if made of hard aluminum, 15 per cent is added. 

The Extras, for which additional charge is made, are as follows: 

Solid Silver Graduations : 

On horizontal circle $10 00 

Verniers, reading to 30" 10 00 

20" 20 00 

Gradienter attachment 5 00 

Stadia hairs, fixed 3 00 

" adjustable 10 00 

Variation plate 10 00 

Arrangement for offsetting right angles 5 00 

Striding level to axis of telescope 20 00 

* Reversion level for telescope 10 00 

Constructed with three leveling screws on base-plate, instead of four 10 00 

Three-leveling-screw shifting center 5 00 

Extra extension tripod in lieu of ordinary 5 00 

Protection bag 1 00 

Bottle of fine watch oil 25 

The Reversion Level. 

* The REVERSION LEVEL is ground on both sides, and the case open on 
top and bottom, so that the bubble is always visible when the telescope is revolved 
in transit. Absolute levels may be obtained, and errors in adjustment may be 
corrected in reversion, by a method of vertical double centering. 



THE A. LIETZ COMPANY 



131 




No. 3. 
COMPLETE ENGINEERS' TRANSIT. 

WITH VERTICAL ARC. 

Price, $230.00. 

S3T For details and extras see 'the following page. 
The 5-inch vertical arc is provided with a double vernier reading to minutes. 



132 MODERN SURVEYING INSTRUMENTS. 



No. 3. 
Dimensions and Weight. 

Horizontal Circle (measured to edge of graduation) 6^4 inches diam. 

Vertical Arc (measured to edge of graduation) 5 

Compass Needle \ x / 2 " long- 
Object Glass 1% " diam. 

Telescope 11 " long 

Magnifying power 24 

Weight of instrument 15 lbs. 

tripod S l / 2 " 

box 8 " 

Weight of this instrument if made of hard aluminum l Y / 2 " 

The price of this instrument as shown is $230 00 

And if made of hard aluminum, 15 per cent is added. 

The Extras, for which additional charge is made, are as follows: 

Solid Silver Graduations : 

On horizontal circle $10 00 

On vertical arc 5 00 

Verniers, reading to 30" on horizontal circle 10 00 

20" " " 20 00 

Gradienter attachment 5 00 

Stadia hairs, fixed 3 00 

" • adjustable 10 00 

Variation plate 10 00 

Arrangement for offsetting right angles 5 00 

Striding level to axis of telescope 20 00 

Reversion level to telescope (see footnote, page 130) 10 00 

Constructed with three leveling screws on base-plate, instead of four 10 00 

Three-leveling-screw shifting center 5 00 

Prism, attachable to eyepiece 8 00 

Extra extension tripod in lieu of ordinary 5 00 

Protection bag 1 00 

Bottle of fine watch oil 25 

Saegmiiller solar attachment of aluminum 50 00 



THE A. LIETZ COMPANY. 



133 




A. LIETZ CO, 

Makers 
Sau Francisco 



No. 4. 
COMPLETE ENGINEERS' TRANSIT. 

WITH FULL VERTICAL CIRCLE. 

Price, $235.00. 

£2T For details and extras see the following page. 
The 5-inch vertical circle is provided with a double vernier, reading to minutes. 



134 MODERN SURVEYING INSTRUMENTS. 



No. 4. 
Dimensions and Weight. 

Horizontal Circle (measured to edge of graduation) 6^4 inches diam. 

Vertical Circle (measured to edge of graduation) 5 " 

Compass Needle \y 2 " long 

Object Glass 1% " diam. 

Telescope 11 " long 

Magnifying power 24 

Weight of instrument 15 lbs. 

tripod Sy 2 " 

box 8 " 

Weight of this instrument if made of hard aluminum 7y 2 " 

The price of this instrument as shown is $235 00 

And if made of hard aluminum, 15 per cent is added. 

The Extras, for which additional charge is made, are as follows: 

Solid Silver Graduations : 

On horizontal circle $10 00 

On vertical circle 5 00 

Verniers, reading to 30" on horizontal circle 10 00 

20" " " 20 00 

Gradienter attachment 5 00 

Stadia hairs, fixed 3 00 

" adjustable 10 00 

Variation plate 10 00 

Arrangement for offsetting right angles 5 00 

Striding level to axis of telescope 20 00 

Reversion level to telescope (see footnote, page 130) 10 00 

Constructed with three leveling screws on base-plate, instead of four 10 00 

Three-leveling-screw shifting center 5 00 

Prism, attachable to eyepiece 8 00 

Extra extension tripod in lieu of ordinary 5 00 

Protection bag 1 00 

Bottle of fine watch oil 25 

Saegmiiller solar attachment of aluminum 50 00 

Guard for vertical circle 5 0C 



THE A. LIETZ COMPANY. 



135 




A. Lietz Company 

Makers 
San Francisco, Cal. 



No. 5. 
COMPLETE TRANSIT-THEODOLITE. 

FOR HIGHEST GRADE ENGINEERING WORK. 
£2T For particulars and price, see the following page. 



I36 MODERN SURVEYING INSTRUMENTS. 

No. 5. Transit-Theodolite. 

This is an instrument of very superior construction. 

The standards upon which the telescope rests are cast in one U-shaped piece, 
thus affording more strength than the ordinary form. 

The telescope is reversible in position, as well as exchangeable in its bear- 
ings, which are provided with dust-caps and screws, to give them the proper 
friction. The telescope is either erect or inverting. For reasons already set 
forth, the inverting form should be given the preference. The telescope possesses 
the finest lenses and optical accessories. It has a slide-protector and is provided 
with a sunshade. The cross-hairs are focused by a screw motion of the eye- 
piece. 

All the graduations are on solid silver. The horizontal circle reads to either 
30, 20 or 10 seconds, by two opposite verniers, near the line of collimation, which 
are supplied with two attached reading-glasses, if desired. The vertical arc or 
circle is graduated to read to 30 seconds. 

The instrument is furnished with either three or four leveling screws, that 
operate through a star-piece, as already described in the case of the other 
instruments. 

The U-shaped casting, constituting the support for the telescope, may be 
either in cloth-finish, or in bright lacquer, like the rest of the instrument. The 
metal finish may be had of any desired color. 

The new Lietz Tripod Coupling is furnished without extra charge. 

The case contains all the usual accessories, such as plumb bob, screw-driver, 
adjusting pins, etc. 

Dimensions and Weight. 

Horizontal Circle (measured to edge of graduation) 6^4 inches diam. 

Vertical Arc or Circle (measured to edge of graduation) 5 

Compass Needle (in box on plate) 3^> long 

Telescope 11 

Object Glass 1% diam. 

Magnifying power 24 

Weight of instrument 16 lbs. 

tripod 8 J / 2 " 

box 8 " 

If made of aluminum, the weight of the instrument is reduced 50%. 
The price of the plain transit-theodolite (without a level, clamp and arc to tele- 
scope) is $240.00, and if made of hard aluminum 15% is added. 

The Extras, which make the instrument more complete, 
are as follows: 

Verniers reading to 20" on a 6*4-inch horizontal circle $10 00 

10" " 7 '; " " 35 00 

A 5-inch vertical arc, reading to minutes 20 00 

A 5-inch full vertical circle, reading to minutes 25 00 

with opposite double verniers, reading to 

minutes 50 00 

Two vernier microscopes 15 00 

Long ground level to telescope, with compound clamp and tangent screw, 

telescope reversible, and supplied with gradienter attachment 40 00 

Reversion level for telescope (see footnote, page 130) 10 00 

Striding level 20 00 

Stadia hairs, fixed 3 00 

" adjustable 10 00 

Box needle, on plate 20 00 

Constructed with three leveling screws on base-plate, instead of four 10 00 

Three-leveling-screw shifting center 5 00 

Prism, attachable to eyepiece 8 00 

Protection bag 1 00 

Bottle of fine watch oil 25 

Saegmiiller solar attachment of aluminum 50 00 

Guard for vertical circle 5 00 



THE A. LIETZ COMPANY. 



137 




A. I.ietz Co. 

Makers 
San Francisco 



No. 9. 

COMPLETE MOUNTAIN AND MINING TRANSIT. 

Nos. 6 to 9. 

No. 6 is the Plain Mountain and Mining Transit. 
Xo. 7, the same as No. 6, with telescope level. 
No. 8, the same as No. 7, with a vertical arc. 

33HT For details, prices and extras, see the following page. 



I38 MODERN SURVEYING INSTRUMENTS. 

Nos. 6 to 9. Small Mountain and Mining Transit. 

The Plain Transit. 

This is a beautiful instrument, made to correspond in every way with No. 1, 
except in size and weight. It is a superior and reliable article for general land 
surveying, and particularly for mining purposes. 

Dimensons, Nos. 6 to 9. 

Horizontal circle (measured to edge of graduation) 5 inches diam. 

Vertical arc or circle (measured to edge of graduation) 4 

Compass needle V/2 ' long 

Object glass 1 " diam. 

Telescope 8 long 

Magnifying power 18 

Weight of instrument S J / 2 lbs. 

tripod 6 " 

box 6 

Weight of this instrument if made of hard aluminum A]/ 2 " 

The price of the plain transit, No. 6, is $180 00 

With level to telescope and tangential movement, No. 7 210 00 

With vertical arc in addition, No. 8 225 00 

With full vertical circle, No. 9 230 00 

And if made of hard aluminum, 15 per cent is added. 

The Extras, for which additional charge is made, are as follows: 
Solid Silver Graduations : 

On horizontal circle $10 00 

On vertical arc or circle 5 00 

Gradienter attachment 5 00 

Stadia hairs, fixed 3 00 

adjustable 10 00 

Variation plate 10 00 

Arrangement for offsetting right angles 5 00 

Striding level to axis of telescope 20 00 

Reversion level to telescope (see footnote, page 130) 10 00 

Constructed with three leveling screws on base-plate, instead of four 10 00 

Three-leveling-screw shifting center 5 00 

Prism attachable to eyepiece 8 00 

Half-length tripod 13 00 

Extra extension tripod 15 00 

Extension tripod in lieu of the ordinary 5 00 

Detachable side telescope 35 00 

Lamp for mining engineering, of brass, with ground lens 7 00 

Reflector, for illuminating cross-hairs 4 00 

Plummet lamp 10 00 

Large plumb-bob, weight 4 lbs., for use in shafts 5 00 

Protection bag 1 00 

Bottle of fine watch oil 25 

Saegmiiller solar attachment of aluminum 50 00 

Guard for vertical circle 5 00 



THE A. LIETZ COMPANY. 1 39 

No. 10. Mining Transit. 

The same dimensions as in Nos. I to 4. Graduations on solid 
silver ; verniers, reading to minutes, provided with glass shades ; 
5-inch full vertical circle ; spirit level, clamp and tangent screw to 
telescope; extension tripod, etc. Price, $258.00. If made of hard 
aluminum, 15% added. 

No. 11. Mining Transit. 

The same dimensions as in Nos. 6 to 9. Graduations on solid 
silver ; verniers, reading to minutes, provided with glass shades ; 
4-inch full vertical circle ; spirit level, clamp and tangent screw to 
telescope; extension tripod, etc. Price, $253.00. If made of hard 
aluminum, 15% added. 

It must be apparent that there cannot be any great difference 
in price between a large and a small-sized instrument. The work- 
manship in each is alike, and, if anything, more complicated and 
costly in the smaller. The only difference is in the quantity of 
metal used, but as this cannot possibly amount to much in price, it 
is more than compensated by the additional care required in hand- 
ling the smaller parts. This explanation would hardly seem neces- 
sary, were it not for the prevailing impression that all merchantable 
articles of the same kind should be rated by their respective sizes. 
That this cannot obtain in the case of instruments must stand to 
reason. The price of a transit can only be reduced by omitting cer- 
tain features, or by changing it to a simpler construction. 

No. 12. Mountain and Mining Transit. 

The illustration on page 141 represents our Mountain and 
Mining Transit, No. 12. While with the introduction of our special 
aluminum alloy we have been the producers of the lightest instru- 
ments for years, yet some of our patrons have expressed a desire 
to possess an instrument of smaller size, admitting of easier trans- 
portation in mountainous country. Transit No. 12 is made with 
as much care as our larger instruments ; the constructive details 
are similar, and full reliance may be placed upon this instrument 
as to the performance of its working parts in every respect. We 
would especially recommend our friends to order this instrument in 
our special aluminum alloy, which not only makes it lighter, but 
which adds considerably to the rigidity, lateral strength, and to its 
steadiness. This statement is made and based upon our experience 
gained in the last fifteen years, during which time we have manu- 



140 MODERN SURVEYING INSTRUMENTS. 

factured almost one thousand instruments of our special aluminum 
alloy, and it is verified by authorities who constantly use them. 
At first thought the statement may seem paradoxical that an instru- 
ment made of lighter material should be steadier than one made 
of heavier metals, and we are constantly confronted with queries 
from engineers, when we recommend instruments of the lighter 
type, whether these will prove steady enough in the wind. It 
seems that the ordinary opinion is not based upon practical ex- 
perience, but created by the reasonable assumption that heavier 
weight will offer more resistance to disturbing influences than 
light weight. 

While it cannot be denied that the weight of an instrument 
adds to its steadiness, it must be borne in mind that instruments 
have not been made of the older metals in order to gain steadiness, 
but simply because this was the best material available for the 
purpose. Wear and resistance in case of accident were the principal 
features sought. A light material, provided it has these qualities, 
offers the best opportunity to produce the most rigid instrument, 
for the reason that it admits of lowering the center of gravity by a 
judicious distribution of the metals, and this is what we have aimed 
at, and believe we have fully accomplished in our aluminum alloy 
instruments. This instrument is rigid and firm ; it offers more 
resistance in case of a fall than the heavier metals ; its wearing 
qualities are such that no bushing is required ; the coefficient of 
expansion and contraction is eliminated, so that their adjustments 
will remain constant under severe conditions. Their qualities dur- 
ing the last fifteen years have been so thoroughly tested that we 
conscientiously recommend them to the profession. 



THE A. LIETZ COMPANY. 



141 




142 MODERN SURVEYING INSTRUMENTS. 



No. 12. Mountain and Mining Transit. 

It possesses a double center, lower clamp and tangential move- 
ment, plate movement with the clamp and tangent screw, and sensi- 
tive plate levels ; two double verniers reading to minutes, placed 
conveniently for reading without stepping from the eye-piece end. 
The telescope is reversible, has a clamp and tangent movement, long 
level and vertical circle with double vernier reading to single min- 
utes. The telescope is either erect or inverting. It possesses the 
finest lenses and optical accessories. The cross-hairs are focused 
by a screw motion to the eyepiece. 

Horizontal and vertical graduations are on solid silver. The 
instrument has a Lietz Tripod Coupling and a shifting center. The 
case contains all the usual accessories, such as screw-driver, adjust- 
ing pin, reading glass, etc. 

Dimensions and Weight. 

Horizontal circle, measuring to the edge of graduation 4 inches diam. 

Vertical arc or circle " 4 " 

Compass needle 2y 2 ' long 

Obj ect glass 1 diam. 

Telescope 8 " long 

Magnifying power 18 

Weight of instrument 5 lbs. 

tripod 5 " 

" box 4 " 

Price of instrument $228 00 

If made of hard aluminum 250 00 

Extras for which additional charge is made : 

Gradienter attachment $ 5 00 

Stadia hairs, fixed 3 00 

Variation plate 10 00 

Reversion level to telescope (see footnote, page 130) 10 00 

Prism to eyepiece 8 00 

Half-length tripod 13 00 

Extension tripod in lieu of ordinary 5 00 

Detachable side telescope 35 00 

Guard for vertical circle 5 00 

Vertical circle graduated on the periphery admitting a reading of the 

vernier from the front of eyepiece end 10 00 



THE A. LIETZ COMPANY 



143 




A. LIETZ CO- 
MAKERS 
SAN FRANCISCO 



No. 13. 
COMPLETE TRANSIT-THEODOLITE. 

$2W For details and price see the following page. 



144 MODERN SURVEYING INSTRUMENTS. 

No. 13. Transit Theodolite. 

This instrument is of the same type and embodies the same 
characteristics as our No. 5. It is only of a smaller and more 
portable size. It possesses a double center, lower clamp and tan- 
gential movement; plate movement with the clamp and tangent 
screw, and sensitive plate levels ; double verniers reading to min- 
utes, placed conveniently for reading without stepping from the 
eye-piece end. The telescope is reversible in position, as well as 
exchangeable in its bearings, which are provided with dust caps, 
and screws, to give them the proper friction. The telescope is 
either erect or inverting. For reasons already set forth, the invert- 
ing form should be given the preference. The telescope possesses the 
finest lenses and optical accessories. It has a slide-protector and is 
provided with a sunshade. The cross-hairs are focused by a screw 
motion to the eye-piece. 

All the graduations are on solid silver, reading to single min- 
utes, the horizontal circle by two opposite verniers, near the line 
of collimation, the vertical arc by one double vernier. The instru- 
ment has the Lietz tripod coupling and a shifting center. The case 
contains all the usual accessories, such as plumb-bob, screw-driver, 
adjusting pin, reading-glass, etc. 

DIMENSIONS AND WEIGHT. 

Horizontal circle measured to the edge of the graduation, 5 
inches diameter ; vertical circle measured to the edge of the gradu- 
ation, 4 inches diameter; telescope, 8 inches long; object glass, 
1 inch diameter; magnifying power, 18. Weight of the instru- 
ment, Sy 2 pounds ; weight of tripod, 6 pounds ; weight of box, 
6 pounds ; weight of instrument, if made of hard aluminum, 4^2 
pounds. Price of this instrument, complete as above, $257.00, and, 
if made of hard aluminum, 15% is added. 

The extras, for which additional charges are made, are as follows : 

Vernier, reading to 30" on the horizontal circle $10 00 

Two vernier microscopes 15 00 

Reversion level to telescope (see footnote, page 130) 10 00 

Striding level 20 00 

Stadia hairs, fixed 3 00 

Box needle on plate 20 00 

Constructed with three leveling screws on base-plate, instead of four 10 00 

Three-leveling-screw shifting center 5 00 

Extension tripod in lieu of ordinary 5 00 

Saegmiiller solar attachment , 50 00 

Guard for vertical circle 5 00 



THE A. LIETZ COMPANY. 



145 




No. 16. 
COMPOUND MINING AND SOLAR TRANSIT. 

Price, Complete, $318.00. 

$3W For details see the following page. 



I46 MODERN SURVEYING INSTRUMENTS. 

No. 16. Compound Mining and Solar Transit. 

This instrument is like No. 4, with the Saegmuller Solar Attachment. 

It possesses a double center, lower clamp and tangential movement; plate 
movement with clamp and tangent screw, and sensitive plate levels ; double ver- 
niers reading to minutes, placed conveniently for reading, without stepping from 
the eye end. Compass needle and graduated compass ring, with variation plate. 
Cloth-finished standards, carrying an improved telescope. The telescope is re- 
versible and evenly balanced ; it affords ample definition, power and light ; fixed 
stadia hairs are supplied ; it has a long level and possesses a clamp and tangential 
movement ; also gradienter attachment ; a full or half vertical circle reading to 
minutes. All graduations are on solid silver. The instrument has the Lietz 
tripod coupling, and a shifting center. 

The solar attachment is detachable, screws into the top of the telescope axis, 
and becomes a part of the instrument. It answers all the purposes of a side 
telescope, as shown in the marginal sketch. 

The whole instrument is packed in a handsome case, with a special place for 
the solar attachment, containing a plumb bob, adjusting pins and all the usual 
accessories. 

Dimensions and Weight. 

Horizontal circle (measured to edge of graduation) 6% inches diam. 

Vertical arc or circle (measured to edge of graduation) 5 

Compass needle 4^ long 

Telescope 11 

Object glass \% " diam. 

Magnifying power 24 

Weight of instrument 16 lbs. 

tripod Sy 2 " 

box 8 " 

Weight of this instrument if made of hard aluminum 8 

The price of this instrument, complete, is $318 00 

And if made of hard aluminum, 15 per cent is added. 

The extras, for which additional charge is made, are as follows : 

Verniers, reading to 30" on horizontal scale $10 00 

20" " " 20 00 

Adjustable stadia hairs 10 00 

Arrangement for offsetting right angles 5 00 

Striding level to axis of telescope 20 00 

Constructed with three leveling screws on base-plate, instead of four 10 00 

Three-leveling-screw shifting center 5 00 

Prism attachable to eyepiece 8 00 

Extra extension tripod 15 00 

Extension tripod in lieu of the ordinary 5 00 

Reversion level on telescope (see footnote, page 130) 10 00 

Half-length tripod 13 00 

Detachable side telescope 35 00 

Lamp for mining engineering, of brass, with ground lens 7 00 

Reflector for illuminating cross-hairs 4 00 

Plummet lamp 10 00 

Large plumb-bob, weight 4 lbs., for use in shafts 5 00 

Protection bag 1 00 

Bottle of fine watch oil > 25 

Guard for vertical circle 5 00 



THE A. LIETZ COMPANY. 



147 




A. I^ietz Company 

Makers 
San Francisco, Cal. 



No. 17. 
COMPOUND MINING AND SOLAR TRANSIT. 

Price, Complete, $313.00. 

SW For details see the following page. 



I48 MODERN SURVEYING INSTRUMENTS. 

No. 17. Compound Mining and Solar Transit. 

This instrument is like No. 9, with the Saegmiiller solar attachment. 
It possesses a double center, lower clamp and tangential movement; plate 
movement with clamp and tangential screw, and sensitive plate levels ; double 
verniers reading to minutes, placed conveniently for reading without stepping 
from the eye end. Compass needle and graduated compass ring, with variation 
plate. Cloth-finished standards, carrying an improved telescope. The telescope 
is reversible and evenly balanced ; it affords ample definition, power and light ; 
fixed stadia hairs are supplied ; it has a long level and possesses a clamp and 
tangential movement ; also gradienter attachment ; a full or half vertical circle 
reading to minutes. All graduations are on solid silver. The instrument has the 
Lietz tripod coupling and a shifting center. 

The solar attachment is detachable, screws into the top of the telescope axis, 
and becomes a part of the instrument. It answers all the purposes of a side 
telescope, as shown in the marginal sketch. 

The whole instrument is packed in a handsome case, with a special place for 
the solar attachment, containing a plumb-bob, adjusting pins and all the usual 
accessories. 

Dimensions and Weight. 

Horizontal circle (measured to edge of graduation) 5 inches diam. 

Vertical circle (measured to edge of graduation) 4 " 

Compass needle , 3 T / 2 ' long 

Telescope 8 

Obj ect glass 1 " diam. 

Magnifying power 18 

Weight of instrument 9 lbs. 

tripod 6 " 

Weight of this instrument if made of hard aluminum 5 ' 

The price of this instrument, complete, is $313 00 

And if made of hard aluminum, 15 per cent is added. 

The Extras, for which additional charge is made, are as follows: 

Adjustable stadia hairs $10 00 

Arrangement for offsetting right angles 5 00 

Striding level to axis of telescope 20 00 

Reversion level for telescope (see footnote, page 130) 10 00 

Constructed with three leveling screws on base-plate, instead of four 10 00 

Three-leveling-screw shifting center 5 00 

Prism attachable to eyepiece 8 00 

Extra extension tripod 15 00 

Half-length tripod 13 00 

Extension tripod in lieu of the ordinary 5 00 

Detachable side telescope 35 00 

Lamp for mining engineering, of brass, with ground lens 7 00 

Reflector, for illuminating cross-hairs 4 00 

Plummet lamp 10 00 

Large plumb-bob, weight 4 lbs., for use in shafts 5 00 

Protection bag 1 00 

Bottle of fine watch oil 25 

Guard for vertical circle 5 00 



THE A. LIETZ COMPANY. 



149 



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en * | 

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X 



I50 MODERN SURVEYING INSTRUMENTS. 



No. 19. Engineers' Y-Level. 

Possesses all recent improvements. Long center; star-shaped construc- 

tion of the guide for the foot-screws ; clamp and tangential movement ; sensitive 
spirit level. The telescope has definition, light and power in a high degree; best 
achromatic Jena glass lenses (erect vision) and stadia hairs if desired; is pro- 
vided with a slide-protector, and either cloth, bright or bronze finished. Fast- 
ened to the tripod by means of the Lietz coupling. 

The whole is packed in a neat case containing all the usual accessories. 

Dimensions and Weight. 

Length of telescope 18 inches 

Diameter of objective l}i " 

Magnifying power 33 

Weight of instrument 10^ lbs. 

tripod 8 

box 7y 2 " 

Weight of this instrument if made of hard aluminum 6^4 ' 

The price of this instrument is $140 00 

And if made of hard aluminum, 15 per cent is added. 

The Extras, for which additional charge is made, are as follows: 

Mirror, to control the bubble at eye end $10 00 

Stadia hairs, fixed 3 00 

adjustable '. ! . . 10 00 

Agate-fitted Y's ! ... 10 00 

Reversion level to telescope (see footnote on page 130) 15 00 

Three leveling screws on base-plate, instead of four 10 00 

Protection bag 1 00 

Bottle of fine watch oil 25 

£^° If this instrument is provided with a micrometer screw for the vertical 
control of one of the Y's, and an additional spirit level, set normal to the line of 
collimation, it becomes a HYDROGRAPHIC Y-LEVEL. The charges for these 
additions are $40.00. 



THE A. LIETZ COMPANY. 



151 




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152 MODERN SURVEYING INSTRUMENTS. 



No. 20. Engineers' Dumpy Level. 

Long center and most approved construction of the lower parts. Sen- 
sitive spirit level, placed over the telescope, to lower the center of gravity. 
The telescope has definition, light and power in a high degree ; best achromatic 
Jena glass lenses, erect vision and stadia hairs if desired. Is provided with a 
slide-protector and cloth finished. Screw coupling. 

Packed in a neat case containing all the usual accessories. 

This is an elegant instrument, fit for the best class of engineers' work, and is 
guaranteed in every detail. 

Dimensions and Weight. 

Length of telescope 15 inches 

Diameter of objective 1-Hs 

Magnifying power 28 

Weight of instrument 9 lbs. 

tripod 8 " 

box sy 2 " 

The price of this instrument is $100 00 

No. 20 A. 

Is the same as No. 20, but provided with a mirror to indicate the position of 
the bubble to an observer at the eye end. 

Price $110 00 

The Extras to Nos. 20 and 20a, for which additional charge is made, 

are as follows: 

Stadia hairs, fixed $3 00 

Horizontal circle, reading to minutes 25 00 

Protection bag 1 00 

Bottle of fine watch oil 25 



THE A. LIETZ COMPANY 



153 




Xo. 21. 
BUILDERS' LEVEL. 

£5T For price and details, see the following page. 



A. Lietz Company 

Makers 
Ssan Francisco, Cal. 




Xo. 21. 

Fitted with a Right- Angle Bracket 
and Control Level for Vertical 
Sights. 

Extra Charge, $15.00. 



154 MODERN SURVEYING INSTRUMENTS. 



No. 21. Builders' Level. 

Constructed by us for the use of architects, builders, contractors, and for gen- 
eral engineering work not requiring the highest degree of accuracy. The instru- 
ment is very substantially made, and not liable to get out of order easily ; an im- 
portant feature, because instruments of this kind occasionally have to be intrusted 
to men whose duties will not permit to take the greatest amount of care. The 
instrument is far superior to the so-called architects' level, which is built on the 
principle of the'Y-level, having other so-called patented features, which make 
the instrument complicated and unreliable, difficult to manipulate, and which 
decrease its strength considerably. Our instrument No. 21 is built for the special 
purpose of obtaining the simplest form of an accurate and reliable tool. Packed 
in a neat case containing all the usual accessories. 

Dimensions and Weight. 

Length of telescope 12 inches 

Diameter of objective 1% " 

Magnifying power 18 

Weight of instrument 4 T / 2 lbs. 

tripod " 6 

box zy A " 

The price of this instrument is $45 00 

When supplied with a horizontal circle graduated to J/2 degrees 
$5.00 additional is charged. 

This instrument can also be supplied with our Patent Angle Bracket, as 
shown in the previous page. 

Extra for this attachment, $15.00. 



THE A. L1ETZ COMPANY. 



155 



A. Lietz Company 

Makers 
San Francisco, Cal. 



%, 





No. 22. 
LIETZ PRELIMINARY TRANSIT. 

(Patented) 
For details and price see following page. 



No. 22. 

Shown as supplied with Extension Bar 

for Incline Sights. 

Extra Charge, $5.00. 



156 MODERN SURVEYING INSTRUMENTS. 

No. 22. Lietz Preliminary Transit. 

[Patent applied for.] 

Price of instrument as shown on page 155 with tripod and 
box, containing all the usual accessories, such as plumb-bob, screw- 
driver, reading-glass, etc., $60.00. The extras for which additional 
charge is made are as follows : 

Stadia hairs, fixed , $3 00 

Extension tripod in lieu of ordinary 2 50 

Dimensions and Weight. 

Length of telescope 6 inches 

Diameter of objective 3^ " 

Length of needle 3^4 " 

Diameter of horizontal plate 3 " 

Magnifying power to telescope (diameters) 4 

Weight of the instrument 2 lbs. 

case 2 

tripod iy 2 " 

This Transit when used as a needle instrument admits to lay- 
off the magnetic variation, so that the combination incorporates a 
variation plate. 

No. 22. The Lietz Preliminary Transit. 

For many purposes where great accuracy is not requred, it is 
often far more convenient to use some small instrument which will 
admit of measurements within practical limits. The irrigator, 
farmer, ditcher, grader, building contractor, gardener, forester, road 
builder, etc., often require means of obtaining heights and relative 
positions, for which higher grade instruments would be unnecessarily 
refined. 

It is for the use of such men that we have constructed the Lietz 
Preliminary Transit. This combines portability with accuracy and 
reliability, within a reasonable limit, at a minimum expenditure. 
In appearance it is identical to an engineer's transit. It possesses 
four leveling screws, but no shifting center. The lower axis moves 
in the star piece which carries the four leveling screws. It is readily 
clamped in any position by means of a milled-head screw, working 
directly on the center. The second spindle carries the top plate 
together with the standards and telescope. The compass is cen- 
trally located, and has a diameter of 3 inches. The plate is gradu- 
ated into quadrants, in the regular way, and this graduation is 
utilized for reading horizontal angles, by means of a vernier, to 2 



THE A. LIETZ COMPANY. 1 57 

minutes of arc. The vertical arc is graduated from o degree to ioo 
degrees each way, reading to 2 minutes by a vernier which is 
clamped readily into any position on the telescope axis by a milled- 
head screw, so that the position of the arc, which is stationary on 
the standard, admits of reading any vertical angle, by means of 
repetition, if over 90. The telescope is 6 inches long, has erect 
lenses, magnifying 4 diameters. The cross-hairs inside the tele- 
scope are not adjustable. We found this quite an improvement in 
this class of instruments. They are so set that the line of collima- 
tion cannot be deranged, except by a heavy fall, when the telescope 
axis would be bent. Stadia wires may be inserted. The telescope 
possesses a level 2 l / 2 inches in length, and a tangential movement, 
so that the instrument represents a complete transit of modern 
construction, having, of course, a limited degree of accuracy, but 
capable of carrying out preliminaries where high-grade instruments 
would otherwise have to be used. Its cost is within the reach of 
all, and we know of no instrument better adapted to the use of the 
student than one of these complete little field instruments with 
which so much can be accomplished and so much can be learned. 
Every feature of the transit is represented here, and it admits of 
obtaining results approaching those of the surveyor's transit and 
level. 

Crude instruments are placed on the market to supply the 
demand for a fairly reliable measuring tool of small cost. These 
are usually worthless, as they are made without any regard for the 
underlying principles that should govern the make of such an article. 
But with the Lietz Preliminary Pocket Instrument, for which patent 
has been applied, the object has been attained. Every part is care- 
fully made and neatly finished, and its cost is less in comparison 
than the inferior articles that are usually offered for sale in the market. 



I58 MODERN SURVEYING INSTRUMENTS. 

The Johnson Plane Table Outfit, No. 30. 

Johnson's improved plane-table movement, mounted on large tripod $ 45 00 

Plane-table drawing board, 31x24 inches, fitted with screw sockets and 

clamps for paper 5 00 

Plumbing arm and plummet 4 00 

Combined compass and levels 15 00 

Alidade with 11-inch Telescope, with stadia, 4^-inch vertical circle and 

vernier to one minute, ground level, clamp and tangent screw 90 00 

Total $159 00 



Tripods. 




No. 


35. 


No. 


36. 


No. 


37. 


No. 


38. 


No. 


39. 


No. 


40. 


No. 


41. 



Note 



Hardwood Tripod, for Preliminary Transit, No. 22 $ 5.00 

Hardwood Tripod, for Builders' Levels, No. 21 10.00 

Hardwood Tripod, split leg, for Transits Nos. 6 to 13 12.00 

Hardwood Tripod, split leg, for Transits Nos. 1 to 5, 

Levels Nos. 19 and 20 12.50 

Extension Hardwood Tripod, for Preliminary Transit, No. 22. . . 7.50 

Extension Hardwood Tripod, for Transits Nos. 6 to 13 15.00 

Extension Hardwood Tripod, for Transits Nos. 1 to 5, 

Levels Nos. 19 and 20 15.00 

. — One extension leg on tripods Nos. 37 and 38, add $1.25 to list price. 



THE A. LIETZ COMPANY. 



159 



Illuminating Lamps. 





No. 43 



No. 45. 



No. 42. Lamp for illuminating graduations, cross-wires, etc., for use in 

underground work, common $ 4.00 

No. 43. Lamp of brass, with ground lens 7.00 

No. 44. Small Plummet Lamp of brass, steel point 8.00 

No. 45. Large " " " " " 10.00 



it 



1 60 



MODERN SURVEYING INSTRUMENTS. 

COMPASSES. 








No. 46. 



No. 


47. 


No. 


48. 


No. 


49. 


Leather 




any 


No. 


50. 


No. 


51. 


No. 


52. 



Surveying Compass, with folding sights, graduated to Yz degrees 
on raised ring, variation plate, two level bubbles, ball joint 
and socket for Jacob staff mountings, needle about 3>4 in., 
in polished mahogany case each $16.00 

Same as No. 46, but without variation plate 10.50 

Same as No. 46, but 4^-inch needle 20.00 

Same as No. 48, but without variation plate 13.00 

case with shoulder strap for either of the above instead of mahog- 

box extra 2.50 

Surveying Compass, like No. 46, without level bubbles ; needle 

about 3 inches 9.00 

Surveying Compass, like No. 46, without level bubbles ; needle 

about 3^2 inches 1 1.00 

Surveying Compass, like No. 46, without level bubbles ; needle 

about 4 inches 11.50 



THE A. LIETZ COMPANY. 



161 



Sight Compasses. 




No. 53. Pocket Compass, bronzed, 2j^-inch bar needle, with stop, silvered 

metal dial, with cover each $5.25 

No. 54. Pocket Compass, bronzed, 3-inch bar needle, with stop, silvered 

metal dial, with cover each 6.25 

No. 55. Pocket Compass, watch pattern, with folding sights, silvered 
metal dial, 1 24-inch bar needle, with stop, graduations on 
raised ring each 4.00 

No. 56. Pocket Compass, watch pattern, with folding sights, silvered 
metal dial, 2-inch bar needle, with stop, graduations on raised 
ring each 4.60 

No. 57. Pocket Compass, watch pattern, with folding sights, silvered 
metal dial, 2* 2-inch bar needle, with stop, graduations on raised 
ring each 5. 10 

No. 58. Pocket Compass, watch pattern, with folding sights, silvered 
metal dial, 2-inch bar needle, with stop, graduations on raised 
ring, with clinometer attachment each 6.50 




No. 60. Pocket Compass, hunting case, self-acting stop, bar needle, V/ 2 - 

inch, silvered metal dial each 2.95 

No. 61. Pocket Compass, hunting case, self-acting stop, bar needle, lf£- 

inch needle, silvered metal dial each 3.20 



1 62 




MODERN SURVEYING INSTRUMENTS. 

Clinometer Compass. 




No. 70. 

No. 71. 
No. 72. 

No. 80. 



No. 



Clinometer Compass, bar needle, with stop, 2^-inch, silvered 

metal dial, having a clinometer, in leather case each $ 7.25 

Clinometer Compass, bar needle, with stop, 3-inch, silvered metal 

dial, having a clinometer, in leather case each 8.75 

Clinometer Compass, bar needle, with stop, 4-inch, silvered 

metal dial, having a clinometer, in leather case each 10.50 

Hutchinson's Improved Pris- Prismatic Compass, 

matic Compass, 3-inch floating- 
card dial, jeweled center, top 
nearly enclosed, in leather 
sling case each $16.00 



Prismatic Compass and Clino- 
meter, 3-inch floating alumi- 
num ring compass, jeweled 
center, gravity clinometer, giv- 
ing inches per yard and de- 
grees each 23.00 




No. 80. 




No. 82. 



THE A. LIETZ COMPANY. 



163 



M. Attwood Mining Clinometer and Compass. 




A NEW POCKET INSTRUMENT. 



No. 87. The accompanying cut represents a new universal measuring tool, 
including Attwood's Mining Clinometer. It combines the most sensitive clinometer 
with two levels, a compass and a sighting arrangement, with reflecting metal mir- 
ror, which permits its use as a hand leveling instrument (similar to Lock's hand 
level), while inclines can be measured by the use of the sight as well as the 
base of the instrument. When held horizontal, the sight also admits of taking 
compass bearings. 

The instrument is especially constructed for the use of miners, to take the 
underlay of any metalliferous vein, the dip of any bed, or stratum of rock, or 
seam of coal. The timbering of any level, shaft or incline may be set by it. 

It can also be used in quartz mills, to give the proper angle to the silvered 
plates, blanket, trays, and sluice boxes. 

The instruments are extensively used in our mining districts, as well as in 
South Africa. The late improvements make it a universal measuring tool 
adaptable to the many uses, underground as well as surface work, which the 
engineer as well as the superintendent or foreman has to perform. 

It is made of aluminum alloy, and weighs, inclusive of leather case, eight 
ounces. 

Price, complete $15.00 



164 



MODERN SURVEYING INSTRUMENTS. 

Hand Levels. 




No. 90. 

No. 90. Locke's Hand Level, bronze, with prism and magnifying lens, 

for bubble, 5-inch, in case $ 7.00 




No. 92. 
No. 92. Square Hand Level, 5-inch, in case. 



4.50 




No. 95. 

No. 95. Abney Level and Clinometer, 5-inch, in case 13.50 

Consisting of a hand level similar to Locke's ; the bubble is mounted on a 
vertical arc, graduated, which is used to obtain angles, slopes, etc. 




No. 96. 
No. 96. Abney Level, like No. 95, with compass, etc. 



18.00 



THE A. LIETZ COMPANY. 



165 



Aneroid Barometers, for Measuring Altitudes and Atmospheric 

Pressure. 





No. 100. 



No. 106. 



No. 100. Watch pattern, gilt, l^-inch silvered metal dial, compensated 
for temperature, revolving altitude scale, 3,000 feet, in 
morocco case each $20.00 

No. 102. Watch pattern, gilt, l^-inch silvered metal dial, compensated 
for temperature, revolving altitude scale, 10,000 feet, in 
morocco case each 19.00 

No. 104. Watch pattern, gilt, 1 ^4-inch silvered metal dial, compensated 
for temperature, revolving altitude scale, 15,000 feet, in 
morocco case each 20.00 

No. 106. Watch pattern, gilt, l?4-inch silvered metal dial, compensated 
for temperature, revolving altitude scale, 10,000 feet, hunting 
case each 22.00 

No. 108. Watch pattern, gilt, l^-inch silvered metal dial, compensated 
for temperature, revolving altitude scale, 15,000 feet, hunting- 
case each 24.00 

No. 110. Watch pattern, gilt, 2^-inch silvered metal dial, compensated 
for temperature, revolving altitude scale, 3,000 feet, in 
morocco case each 21 .00 

No. 111. Watch pattern, gilt, 2^-inch silvered metal dial, compensated 
for temperature, revolving altitude scale, 10,000 feet, in 
morocco case each 20.00 



i66 



MODERN SURVEYING INSTRUMENTS. 




No. 115. 



No. 112. 



No. 115. 



Watch pattern, gilt, 2^-inch silvered metal dial, compensated 
for temperature, revolving altitude scale, 15,000 feet, in 
morocco case each $21.00 

Pocket Aneroid, 2^-inch silvered metal dial, fixed altitude scale, 
5,000 feet, in single 5-foot divisions, in repeating circle of 
divisions, making it possible to read even closer than 5 feet, 

compensated for temperature, in case each 50.00 

A portable form of Surveying Aneroid. 



THE A. LIETZ COMPANY. 

Surveying and Mining Aneroid. 



167 




No. 120. Mining Aneroid, 3-inch silvered 
metal dial, fixed altitude scale, 
2,000 feet below and 4,000 feet 
above sea-level, vernier with rack 
and pinion, reading to 2 feet, ad- 
justable reading lens, compensated 
for temperature, in ' leather sling- 
case each $50.00 



No. 120. 

No. 121. Mining Aneroid, 3-inch silvered metal dial, fixed altitude scale, 
2,000 feet below and 4,000 feet above sea-level, vernier with 
rack and pinion reading to 2 feet, adjustable reading lens, 
compensated for temperature, in aluminum case each 

No. 122. Surveying Aneroid, as above, 10,000 feet, with vernier reading 
t0 5 fee t each 

No. 123. Surveying Aneroid, as above, 10,000 feet, with vernier reading 
to 5 feet, aluminum case each 

No. 124. Surveying Aneroid, as above, 16,000 feet, with vernier reading 
to 5 feet eac h 

No. 125. Surveying Aneroid, as above, 16,000 feet, with vernier reading 
to 5 feet, aluminum case each 

No. 126. Pocket Thermometer, 5-inch, glass scale, reading to 2 degrees 
Fah., in hard rubber or nickel-plated case each 

Barographs and Thermographs. 



60.00 



48.00 



58.00 



50.00 



60.00 



1.00 




No. 128. 

No. 128. Barograph, registering one week, by twentieths inches, from 28 
to 30.5, movement operated by a large vacuum pan concealed 
in the base of the instrument, 8-day clock movement jeweled, 
oak case, with glass sides, top and ends, complete with charts 
for one year, pen and ink each $40.00 



1 68 



MODERN SURVEYING INSTRUMENTS. 




No. 130. 



No. 130. Barograph, large size, all working parts exposed, 8 vacuum 

boxes each $50.00 




No. 135 



No. 135. Thermograph, registering for one week, from 1 to 100 degrees 
Fahrenheit, by 2 degrees, in metal weather-proof case, with 
handle, glass front, eight-day jeweled clock movement, with 
charts for one year, ink and pen each 43.00 



THE A. LIETZ COMPANY. 



169 



No. 137. 



No. 139. 



Thermograph, registering for one week, from 1 to 100 degrees 
Fahrenheit, by 2 degrees, in oak case, with handle, glass front, 
eight-day jeweled clock movement, with charts for one year, 
ink and pen each $40.00 

Thermograph, large size, in oak case each 50.00 



Anemometers. 




No. 142. 



No. 142. Biram Anemometer, 3-inch diameter, reading to 1,000 feet, with 

disconnector, in polished mahogany case each $20.00 




No. 144. 



No. 144. Watch Pattern Anemometer, 2-inch diameter, registering to 
1,000 feet, with disconnector, hunting case, in velvet-lined 
morocco case eacn $30.00 

No. 150. U. S. Weather Bureau Standard Rain Gauge each 10.00 



170 



MODERN SURVEYING INSTRUMENTS. 

The Portable Current Meter. 




This instrument is 
constructed and used for 
the measurement of rate 
or Hozv of small rivers 
and streams, also for the 
flow of tides. 

For this purpose the 
meter should be placed 
in the stream, as per 
directions supplied, and 
allowed to run for a 
given time. The rate of 
the stream per unit time 
is then shown by refer- 
ence to the graduations 
of the circles which are 
actuated by the force of 
the water upon the fan- 
screw. 



No. 152. 



Price 



$45.00 



Water Register. 




As made by us for the United States De- 
partment of Agriculture. 

Recording drum, eight-day clock movement. 

No. 154. Price, complete with cover not 

shown in cut, 12-inch drum. $50.00 

No. 156. 18-inch drum 70.00 

Extra Register Sheets, $4.00 per 100. 



&H 



A. Lietz Co. 

Makers 
San Francisco 



THE A. LIETZ COMPANY. 



171 



176-178 





No. 160-5. 



No. 170-74. 



I 

182-186 



No. 160-5. Leveling Rods. 

«r Note —The leveling rods (160-5) are our own make, graduated to 
hundredths, by uniform, clean divisions. The black numerals corresponding 
to the tenths, have an exact height of 0.06 foot and the red or foot numerals 
are 0.08 foot high. This affords a rod reading at distances where graduation 
lines disappear. The wood is the best, thoroughly seasoned, ^^^et^and 
all connecting metal parts are cast in one piece: 



the vernier made to thou- 
sandths, rtetcalT 7s' bra*ss~ and the "face of the target is japanned. We recom- 
mend this rod as the best in the market. It is a self-reading rod, similar to the 
Philadelphia pattern. 



1^2 MODERN SURVEYING INSTRUMENTS. 

Leveling Rods. 

No. 160. Philadelphia Leveling Rod, improved type, divided in lOths and 
lOOths of a foot, with vernier reading to lOOOths, 8 feet sliding 
out to 15 feet $17.00 

No. 161. Philadelphia Leveling Rod, improved type, divided in lOths and 
lOOths of a foot, with vernier reading to lOOOths, 7 feet sliding 
out to 13 feet 16.00 

No. 162. Philadelphia Leveling Rod, improved type, divided in lOths and 
lOOths of a foot, with vernier reading to lOOOths, 6y> feet 
sliding out to 12 feet 16.00. 

No. 163. Philadelphia Leveling Rod, improved type, divided in lOths and 
lOOths of a foot, with vernier reading to lOOOths, 5 feet sliding 
out to 9 feet 15.00 

No. 164. Philadelphia Leveling Rod, improved type, divided in lOths and 
lOOths of a foot, with vernier reading to lOOOths, 4 feet sliding 
out to 7 feet 15.00 

No. 165. Philadelphia Leveling Rod, improved type, divided in lOths and 
lOOths of a foot, with vernier reading to lOOOths, 3 feet sliding 
out to 5 feet 13.50 

No. 170. Philadelphia Leveling Rod, block graduation, alternately black 
and white, in lOths and lOOths, with vernier reading to 
lOOOths, 7 feet sliding out to 13 feet each 15.00 

No. 172. Philadelphia Leveling Rod, light, block graduation, alternately 
black and white, in lOths and lOOths, with vernier reading to 
lOOOths, 6y 2 feet sliding out to 12 feet each 14.00 

No. 174. Philadelphia Leveling Rod, mining, block graduation, alternately 
black and white, in lOths and lOOths, with vernier reading to 
lOOOths, 3 feet sliding out to 5 feet each 12.00 

No. 176. Architects' Rod, hardwood, engine divided in feet and 8ths of 

an inch, with vernier reading to 64ths each 6.00 

No. 178. Architects' Rod, hardwood, engine divided in lOths and lOOths 

of a foot, with vernier reading to lOOOths 6.00 

Flexible Rods. 




W<WM0*fi!®nVh 




No. 180. 
For Leveling and Stadia Work. 

Painted on canvas, with a legible design to read to hundredths of a foot. 
The numerals of the tenths are black and one-tenth of a foot high ; the foot 
numerals are red and two-tenths of a foot high. Length, 10 or 12 feet. May be 
rolled up in a package 2y 2 to 3 inches long (the width of the canvas), and less 
than \y 2 inches in diameter, weighing less than 3 ounces. A very handy requisite 
on along trip. 

Price, 10 feet long $3.25 

Price, 12 feet long 4.00 



THE A. LIETZ COMPANY. 173 

Ranging Poles. 

No. 182. Wooden pole, 6 and 8 feet long, with steel pointed shoe, divided 

in feet, red and white alternately each $2.25 

No. 184. Octagonal steel spear, 6 to 8 feet long, divided in feet, red and 

white alternately each 2.75 

No. 186. Of half-inch iron pipe, with pointed steel shoe, divided in feet, red 

and white alternately each 2.75 



Rod Level. 




No. 190. 



No. 190. Improved Rod Level each $2.50 

This Rod Level is an improved type, used to hold rod or pole of any shape 
perpendicular. The level bubbles are sunk in the casting at right angles to each 
other, thereby lessening the possibility of breakage, as well as making it easier 
for the rodman to hold the bubbles in the center, than the old form of circular 
spirit levels. The latter are continually leaking and it is impossible to keep 
them in order. 

The Improved Rod Level can either be fastened to the rod by means of a 
flat-head screw, for which there is a key slot provided, or pressed against the rod 
or pole while holding. Indispensable for stadia work. 



174 



MODERN SURVEYING INSTRUMENTS. 

Plumb-bobs. 

Brass Plumb-bob, steel point and screw cap 




Nos. 191-95. 



Nos. 196-204. 



No. 191. About 6 oz., short neck $1.50 

No. 192. " 8 oz. " " 1.75 

No. 193. " 10 oz. " " 2.00 

No. 194. " 14 oz. " " 2.25 

No. 195. " 16 oz. " " 3.25 

No. 196. " 6 oz., long neck 1.50 

No. 197. " 8 oz. " " 1.75 

No. 198. " 10 oz. " " 2.00 

No. 199. " 14 oz. " " 2.25 

No. 200. " 16 oz. " " 2.65 

No. 201. " 20 oz. " " 3.00 

No. 202. " 24 oz. " " 3.25 

No. 203. " 32 oz. " " * 3.75 

No. 204. " 48 oz. " " 5.00 

No. 208. Plain Brass Plumb-bob, 8 oz each .75 

No. 209. " " " " 10 oz each .95 



THE A. LIETZ COMPANY. I75 

Plumb-bob Cord. 

No. 210. Best Braided Linen Cord, thick, medium or thin per yd. $0.02 

No. 211. " " Silk " per yd. .06 

Stake Tacks. 

No. 215. Stake Tacks, galvanized, with indentation on top for guiding the 

point of plumb-bob per lb. $0.60 

Pedometers. 




Nos. 217-19. No. 220. 

Pedometers are pocket instruments for measuring the distance traversed in 
walking, the number of miles being registered by a mechanism inclosed in a 
nickel-plated watchcasing, and operated by the motion of the body. 
No. 217. Pedometer, watch pattern, nickel case, l^-inch, registering 12 

miles by l / A mile. Price . $4.50 

No. 219. The same ; registering 50 miles by 80 yards 5.25 

No. 220. The same ; registering single steps up to 100,000 6.50 

Odometers. 

No. 224. Odometer, for measuring distances by wagon. It is enclosed 
in a brass box, A l / 2 inches diameter, furnished with leathern 
case and double straps to fasten to the center of the wheel. 
It is the most correct instrument for practical use. Price $15.00 

Chain Pins and Markers. 

No. 230. Steel Arrows, 14-inch, 11 in set $1.25 

No. 235. Iron Arrows, 14-inch, 11 in set 60 

No. 240. Marking Tool, timber scribe 1-25 



176 



MODERN SURVEYING INSTRUMENTS. 

Surveyors' Chains. 







No. 245. 
No. 246. 
No. 247. 
No. 248. 
No. 249. 



No. 

No. 
No. 
No. 
No. 
No. 



250. 
251. 

252. 
253. 
254. 

255. 



No. 256. 



Iron Chain, brass handles, No. 8 wire, 33 feet $ 2.60 

" " 50 " 3.25 

u " 66 " 4.00 

" " 100 " 5.25 

Steel Chains, " No. 10 " 33 " 3.50 

" " 50." 4.25 

-" " 66 " 6.50 

" " 100 " 8.00 

Steel Chains, brazed links and ring, No. 12 wire, 33 feet 5.50 

50 " 6.00 

66 " 10.00 

" 100 " 11.00 



Paine's Patent Standard Steel Tapes. 

*4 Inch Wide. 
In iron cases, brass bound, morocco covered, improved handle. 
All orders for Steel Tapes will be filled marked in lOths unless otherwise 
directed. These tapes are marked in links on the other side, if so ordered. 




1 *^_^| 

Manufacturer's Number 204 205 206 207 208 209 

Feet 25 33 50 66 75 100 

No. 290. Price, each $4.00 4.25 5.25 7.00 8.75 10.50 

These tapes are detachable from the case, and are furnished with detachable 
rings to avoid breakage. 

Meters and lOths or 12ths, add 2 cents per foot. 



THE A. LIETZ COMPANY. 



177 



Graduated Compensating Handles. 

For Various Temperatures. 

No. 292. Per pair $2 25 

No. 293. Pocket Thermometers eac ij 115 

No. 294. Grummon's Balance and Level eac h 3 qq 



Steel Spring Tapes, German Silver Cases. 

Graduated in IOths or 12ths. 




DESCRIPTION. 



PRICE, EACH. 

No. 298. Manufacturer's No. 220. 3-foot steel tape, y A inch wide. 



" 221. 


4 


" 1.15 


" 222. 


5 


u 1.30 


" 223. 


6 


" 1.40 


" 224. 


8 


" 1.60 


" 225. 


12 


" 2.25 


" 226. 


15 


" 2.65 



i;8 



MODERN SURVEYING INSTRUMENTS. 



Eddy's Improved Standard Steel Tapes. 

In Leather- Covered Cases, Flush Handle. 




No. 300. 




"Win 

4 

Mlb , 

Nos. 302-4. 

Metal-lined with flush handles, graduated in lOths or 12ths of a foot or 
metric measure. 

No. 300. Manufacturer's Number 210 211 212 213 214 

Feet 33 50 66 75 100 

Price > each $4.15 6.00 8.00 9.50 12.00 

Y% Inch Wide in Red Leather-Covered Cases. 

No. 302. Manufacturer's Number. 300 301 302 303 304 305 306 

Feet 25 33 40 50 66 75 100 

Price ' each $4.50 5.20 6.00 7.20 9.20 10.40 12.80 



THE A. LIETZ COMPANY. 



179 



Eddy's Improved Standard Steel Tapes. 

y 2 Inch Wide in Red Leather- Covered Cases. 

No. 304. Manufacturer's Number 400 401 403 404 

Feet 25 33 50 66 

Price, each $5.10 5.85 8.10 10.35 



405 406 

75 100 

11.70 14.40 



Metallic Warp Tapes. 

These Tapes are made of the best linen tape, with wire threads to prevent 
stretching, and by our process of making are always soft and pliable. The ends 
are reinforced with leather to prevent wearing, and all the cases have our new 
improved flush handle. Graduated in lOths, with links on opposite side. 




Metallic Tape, y & Inch Wide. 

No. 307. Manufacturer's Number .... 137 138 139 140 141 142 143 

Feet 25 33 40 50 66 75 100 

- Price, each $1.75 2.05 2.25 2.45 2.90 3.15 4.00 



Friend Steel Tape, 3/ 8 Inch Wide, in Russet Leather Case, with Brass 

Trimmings. 

Manufacturer's Number 600 601 602 603 

Feet long 50 66 75 100 

Each $4.00 5.00 5.25 7.00 



i8o 



MODERN SURVEYING INSTRUMENTS. 



Star Steel Tapes. 




A cheap but accurate and reliable steel tape. The line is made of the best 
steel, marked and finished in the best style and mounted in a brass case, hand- 
somely nickel-plated. It is light and durable, and easily carried in the pocket, 
and having an improved new handle, winds freely. 

Send for a 4-inch sample piece of the tape. 

When ordering, state if divisions in lOths or 12ths are desired. 



Y% Inch Wide. 
Manufacturer's Number, 497. 25 feet each $3.25 

500. 50 feet each 4.00 

501. 66 feet each 5.00 

502. 75 feet each 5.25 

503. 100 feet each 7.00 



THE A. LIETZ COMPANY. 



181 



Roe's Steel Tape on Patent Electric Reel. 



(Patented May 24, 1892.) 



1A, 

IB, 

2, 

3, 

4, 

5, 

6, 

7 A, 

7B, 



100 ft. long, every ft 

100 " 

100 

100 

66 

66 

66 

50 

50 

50 

50 

33 

33 
200 
200 
200 



End ft. in tenths 
" inches 
5 " u tenths 

5 " " inches 

graduated in links 
in rods and tenths of a rod 
every 5 Iks. Each end every Ik. 
" foot. End ft. in tenths 
inches 
" 5 feet. " " tenths 
5 " " inches 

graduated in links 
every 5 Iks. Each end every Ik. 
foot End ft. in tenths 
inches 
5 feet. " tenths 

5 " inches 

Each meter in decimeter 



200 

10 meters long, 

15 

20 

25 

50 

40 varas long, every vara End vara in lOths 

20 " 

10 " 
300 ft. long, every ft. End ft. in lOths or 12ths 



300 " 


" 5 ft. 


400 " 


" ft. 


400 " 


" 5 ft. 


500 " 


" ft. 


500 " 


" 5 ft. 



PLAIN NICKEL ALUMINUM 
PLATED. PLATED. 



$ 5.00 $ 6.00 $ 7.00 
4.00 5.00 6.00 

5.00 6.00 6.50 



4.00 



3.00 

2.50 
7.50 

6.00 

2.40 

2.70 

3.00 

3.50 

5.00 

4.00 

3.00 

2.40 

10.00 

8.00 

12.50 

10.00 

15.00 

12.00 



5.00 



4.00 

3.00 
9.00 

7.50 

3.00 

3.50 

4.00 

4.50 

6.50 

5.00 

4.00 

3.00 

12.00 

10.00 

15.00 

12.00 

18.00 

15.00 



of 100 foot Electric Reel, without Tape. 

« 2Q0 U « U it « 

Brass Detachable Handles, per pair 



5.50 



4.50 

3.50 
10.50 

9.00 

3.50 

4.00 

4.50 

5.00 

7.50 

6.00 

4.50 

3.50 

14.00 

12.00 

17.50 

15.00 

21.00 

18.00 

1.50 

2.00 

.30 



1 82 



MODERN SURVEYING INSTRUMENTS. 



Eddy's Improved Standard Steel Tapes. 



Empire Steel Tapes. 




With compact brass reel and wooden handle. 

Tapes J4 or $i inch wide, as desired, ^-inch tapes will be sent unless other- 
wise ordered. 

No. 315. Manufacturers' Number 700 701 702 703 

Feet 50 66 75 100 

Price, each $5.65 6.50 9.00 10.15 



THE A. LIETZ COMPANY. 

Surveyors' Chain Tape. 



183 




54-inch heavy Steel Tape, graduated every foot. End foot in lOths on raised 
surface, etched in. 

No. 320. Manufacturer's Number, 5100. 100 feet. Price each $ 6.00 

5150. 150 *' " " 7.50 

5200. 200 " " " 9.00 

5066. 100 links. " " 5.00 

5132. 200 " " " 7.00 

5198. 300 " " " 9.00 

5082M. 25 meters. " " 5.75 

5100M. 30 " " " 6.50 

5164M. 50 " " " 9.50 

5328M. 100 " " " 17.00 

Tape only, without reels, deduct 2.00 

Rings only 50 



Surveyors' Ribbon Steel Tapes. 

Heavy ribbon, ^g-inch steel tape, graduated every foot, end foot in lOths. 

Links have end foot in lOths of links. Meters have first decimeter in millimeters, 

balance of first meter in centimeters, balance of tape in decimeters, on raised 

surface, etched in. 

No. 325. Manufacturer's Number, 4100. 100 feet. Price each $ 7.50 

4150. 150 " " " 9.00 

4200. 200 " "■ " 10.50 

4300. 300 " '-' " 14.00 

4500. 500 " " " 21.50 

4066. 100 links. " " 6.50 

4132. 200 " " " 8.50 

4198. 300 " " " 10.50 

4330. 500 " " " 15.50 

4082M. 25 meters. " " 7.25 

4100M. 30 " " " 8.00 

4164M. 50 " " - 11.00 

4328M. 100 ' 18.50 

Tape only, without reel, deduct 3.50 

Extra rings 50 



184 



MODERN SURVEYING INSTRUMENTS. 




No. 370. 

Above cut shows the new "Punch and Set" combined for repairing steel 
tapes. It cuts a clean hole through two thicknesses of Chesterman or 
Lufkin Tape (or any other of same thickness) one-sixteenth of an inch in 
diameter, without drawing the temper. There is absolutely no filing 
required by this method except to round off the rough corners of the break. 
Place the tape under a small steel spring on the rubber, and it is held in 
place for punching. It is riveted as quickly as the hole is cut. The 
first rivet or eyelet holds the tape in position for cutting or riveting the 
rest. Five minutes is average time to make a good repair. The holes can 
be cut extremely near the ends or edges of repair without any danger of 
splitting the tape, thus avoiding any chance of dirt collecting under the 
splice or cutting the fingers when drawing the tape through the hands or 
catching in rags, etc., when cleaning. 

The tool is small, light, durable, and cheap. It can be carried in the 
instrument box; thus a corps having it with them can repair broken tapes 
with loss of but a few minutes at any time. The cut shows tool, tape, and 
a four-minutes' repair in latter. They are in use and recommended by vari- 
ous railroad companies, city engineers, etc., throughout the country. 

Price of Punch and Set Combined, $2.75, and 1,000 eyelets, $1.25— $4.00 
for outfit. Postage, 16 cents. 



McCullough Tape Level. 




No. 380. 
(Pat. July 26, 1892.) 

Insures accuracy in measurements with steel tapes. Above cut full size. 
Weight, one ounce. It is used by clamping to the tape, about one foot from 
the handle, by means of the two springs shown, and can be attached and 
detached instantly. 
Price $1.00 



THE A. LIETZ COMPANY. 



185 



Engineers' Field Books. 

Our Field Books contain Stadia Reduction Tables, etc. 



No. 460. Field Book, 4x7 inches, 
No. 461. Field Book, 5x8 inches, 



leaves Each $0.55 Doz. $5.40 

leaves Each .60 Doz. 6.00 






No. 463. Mining Transit Book, 4x7 inches, 80 leaves, right hand page 

10 x 10 to one inch Each $0.60 Doz. $6.00 

































































































































































































































































































































































































































































































V 














































1/ 



No. 465. Transit Book, 4x7 inches, 80 leaves Each $0.55 Doz. $5.40 

No. 466. Transit Book, 5x8 inches, 80 leaves Each .60 Doz. 6.00 



1 86 



MODERN SURVEYING INSTRUMENTS. 



No. 470. Level Book, 4x7 inches, 80 leaves Each $0.55 Doz. $5.40 

No. 471. Level Book, 5x8 inches, 80 leaves Each .60 Doz. 6.00 



f SECTION 


A 


STA. 


ELEVA. 


GRADE 


CUT OR FILL 


AREAS 


CUBIC YDS 


REMARKS 


LEFT C RIGHT 


























[ »™»"»' 


«»v 


EHB.NK. 









































































































































































































































No. 474. Field Book, 5^x8 inches, 80 leaves, printed headings. Each...$ 1.00 
Dozen 10.00 



1111111 


t 


I 


|W- 


1 1 ' II! 

ii l-i-j — ' — i — 

ili:::::!!! _._I 


EES # 


IHBI- 


fffrrrrrnTrrrlm 




-A 


if It 


-ii — 4|4-H — i- 

TT TUT T i 


::|:ifi: 


1 1 ll 1 1 1 1 ! 1 1 








mE = P3 : 


_-LJ -J-l-U — L- 4. 


:: £ : +±F : 


f ■j-llll 1 j| II 1 1 1 1 In — 








™ ::::: f : +-+ : 


.IT — Jill — I 


^illl 


t-TttHtt+ttt+M+tT 1 ^ 


lllllllll lllh lllllllllll 1 






Hill I 1 1 


II till 1 


I II 1' II 


TlllllllllltttttmH 



No. 478. Cross-Section Book, Sy 2 x 7y 2 , 80 leaves, ruled 10 x 10. Each. . . .$0.75 
Dozen 7.00 

No. 479. Cross Section Book, 6^ x SV 2 , 80 leaves, ruled 10 x 10. Each. . . .$1.00 
Dozen 10.00 



THE A. LIETZ COMPANY. 



I8 7 



Hensoldt Improved Prism Binoculars. 




HAVE 



1. Greatest brightness of image. 

2. Wide field of view. 

3. Perfect definition, flatness of field, and equal illumination up to the 
margin of the image. 

4. Rigid construction to protect optical parts from any possible 
derangement. 

5. Most compact, light and graceful shape. 

6. Easy access to internal optical parts for cleaning by the user. 
There are a number of prismatic glasses on the market of which some 

have a few of the advantages above mentioned, but only in Hensoldt Im- 
proved Prism Binoculars are all the above points embodied, as may be 
judged by actually comparing the Hensoldt glass with those of other makes. 



1 88 



MODERN SURVEYING INSTRUMENTS. 



Construction. 





Other Construction. 



Hensoldt Improved. 



The novel combined prism of the Hensoldt Binocular is shown in the 
above illustrations, being compared with the other constructions. This 
improved arrangement allows the employment of object glasses of larger 
aperture (up to 2 inches), thereby giving a higher degree of brightness 
than other glasses. It also permits the reduction of the Aluminum Frame to 
the slender shape of a telescope, as well as securing the optical elements 
more rigidly in proper relation to each other. 

The* casing, of Aluminum Alloy, is cast in one piece, making it very 
rigid. It contains no plates fastened with screws, which often become loose 
and are lost. 

Both eye-pieces are focused simultaneously by means of a central screw, 
as in the ordinary field glasses. The difference between the left and right 
eye of an observer can be accommodated for, by the right eye-piece, which 
focuses separately. 




The prism can be removed easily for cleaning. 



THE A. LIETZ COMPANY. 



Prices and Specifications with Solid Leather Sling Case. 



Number 


Magnificatior 
Diameter 


i Object 
Glass 


Field at 
1000 Yds. 


Relative 
Brightness 


Width and 
i Height 


Price 


1 Prism 


Binocular 


sy 2 


H in. 


172 yds. 


18 


3^2x3^4 in. 


$35.00 


2 


" 


6 


1A " 


112 " 


18 


5 x44 " 


46.00 


3 


n 


7 


1A " 


96 " 


13 


5 x44 " 


50.00 


4 


it 


9 


1A " 


76 " 


8 


5 x44 " 


54.00 


5 


a 


12 


1A " 


56 " 


5 


5 x4y 4 " 


62.00 


6 


" 


6 


1^ " 


120 " 


34 


6 x5 " 


60.00 


7 


tt 


10 


2 " 


70 " 


25 


7^x5^ " 


90.00 


8 


it 


12 


2 " 


58 " 


17 


7%x5y 8 " 


95.00 


1 


Monocular 


sy 2 


& " 


172 " 


18 


35^x1 A " 


14.00 


2 


it 


6 


1A " 


112 " 


18 


554x13^ " 


18.50 


3 


a 


7 


1A " 


96 " 


13 


5^x134 " 


19.50 


4 


" 


9 


1A " 


76 " 


8 


514x134 " 


21.50 


5 


a 


12 


1A " 


56 " 


5 


54x134 « 


25.00 


6 


a 


6 


m " 


120 " 


34 


64x2 " 


22.00 


7 


a 


10 


2 " 


70 " 


25 


77/ 8 x2/ 2 " 


35.00 


8 


a 


12 


2 " 


58 " 


17 


7^x24 " 


40.00 



Other Field Glasses of the Ordinary Construction 

Best Qualities. 

No. 490. Field glass, with objectives 2 inches in diameter, leather 

case and strap, low form $15.00 

No. 491. Field glass, with objective 2 inches diameter, leather case 

and strap, high form, with sunshades 16.00 

No. 492. Field glass, with objective 24 inches diameter, leather case 

and strap, high form, with sunshades 18.00 

No. 493. Field glass, with objective 24 inches diameter, leather case 

and strap, low form, with sunshades (NIGHT GLASS). . . 20.00 

No. 494. Field glass (the smallest), with objective 14 inches di- 
ameter, measuring 4x3 inches, with rapid focusing 
arrangement, complete in leather case with strap, with 
sunshades 15.00 



RULES AND REGULATIONS FOR THE GENERAL 

GUIDANCE OF CIVIL ENGINEERS IN 

PROFESSIONAL PRACTICE. 



Established in the Year 1891 by the 
CALIFORNIA ASSOCIATION OF CIVIL ENGINEERS 



Copied From Public Document. 



Section 1. It is desirable, that whenever practicable, all engineer- 
ing services should be charged for on a percentage basis. 

Sec. 2. When no special agreement has been entered into between 
owner or employer, and the engineer who is entrusted with work, the 
latter shall be entitled to compensation for services rendered at not less 
than the minimum percentage rates set forth in the schedule herein- 
after contained; or if the computation of the value of the services on 
a percentage basis is not practicable, then at not less than the minimum 
per diem rate. 

Sec. 3. The various kinds of services rendered by the civil 
engineer are to be classified as follows : 
Preliminaries, 
Plans and Specifications, 
Details, 

Supervision and progress estimates, 
Superintendence, 
Alterations, 
Surveying, 
Professional advice, 
Expert work, 
Consultation. 

Sec. 4. Preliminary work is of such a variety of character that 
it is only then advisable to make a percentage charge for it when little 
or no field work has to be done to secure the necessary data on which 
the preliminary report, design or advice is to be based, and the 
schedule rate applies to such cases only. 






THE A. LIETZ COMPANY. I9I 

In all other cases and for ordinary surveying, whether preliminary 
to construction or otherwise, a salary or a per diem charge should be 
agreed upon. 

Sec. 5. Plans and specifications are required as the basis for the 
letting of contracts, or for the information of the owner, employer or 
consulting engineer, and afford a full description of the work. They 
are implied even when not required by the owner, and the charge 
therefor should not be less than the schedule rates, even when they are 
not actually furnished. They are presumed to include an estimate of 
the cost of the work when such estimate is required. Plans, when 
adopted and approved by owner, should be signed by both owner or 
his agent, and the engineer. 

Sec. 6. Details are not always an essential feature of the engi- 
neer's construction work, and, as the amount of detail work may vary 
greatly, the rate to be charged therefor should be flexible, and rigid 
adherence to the schedule rate is not deemed desirable. 

Sec. 7. Supervision and the making of progress estimates is 
generally, and should always be, required by the owner or employer 
of the engineer who has furnished the plans and specifications, who is 
therefore presumed to be responsible for the work and its proper 
construction. 

Supervision, in the sense in which the word is here used, means 
such inspection from time to time as may be required to satisfy the 
engineer that the specifications are fully complied with. 

When the engineer who has furnished the plans and specifications 
for any work is also the superintendent of construction, as superintend- 
ence is defined in the next section, he shall be entitled to pay for 
superintendence and shall not be entitled to any additional charge for 
supervision. 

Sec. 8. The engineer who designs any work should have a rep- 
resentative on the same as superintendent of construction, or should 
himself be superintendent of construction. But the owner or employer 
is generally, to a greater degree than the engineer, interested in a 
strict compliance by the contractor with the plans and specifications. 
Their interest in the selection of a superintendent of construction is 
mutual, and no person should be selected who is not acceptable to both. 

The schedule rate for superintendence is intended to apply only 
when the engineer who has designed and planned the work superin- 
tends its construction. And this rate includes the compensation only 



192 



MODERN SURVEYING INSTRUMENTS. 



of such assistants or deputies as may be necessary by reason of the 
great extent of any work to represent the engineer himself. All other 
employees are to be paid by the owner. 

Sec. 9. Alterations may be required at any time by the owner of 
the work or may become necessary by reason of unforeseen conditions, 
or by reason of accidents. 

The schedule rate applies only to such alterations as may be re- 
quired by the owner after the original drafts of plans and specifications 
have been submitted and approved, or their approval has been implied 
by the commencement of construction. The planning of alterations 
which become necessary by reason of unforeseen conditions or acci- 
dents to the work are ordinarily covered by the percentage charges 
on the aggregate cost. 

Sec. 10. Surveying covers every class of the engineer or sur- 
veyor's field work which is not necessarily a part of the preliminary 
work as covered by the schedule of minimum rates. It includes all 
location surveys for roads, canals, railroads, etc., besides every class 
of land surveying and land subdivision, and compensation therefor, 
except when, services are covered by schedule rates, should be on a 
salary or a per diem basis. 

Sec. 11. Schedule of minimum charges for civil engineers in 
professional practice: 

TABLE OF MINIMUM CHARGES FOR CIVIL ENGINEERS 



Preliminaries 

Plans and specifications 

Details 

^Supervision 

Superintendence 

t Alterations 

Everything, including superinten 
dence and alterations 



1-1 



1.5 

2.5 

1.0 
1.0 

3-5 

6.0 



9-5 



1.0 
2.0 
1.0 
0.5 
3-o 
5-0 



7-5 



0.8 

1.8 
0.8 
0.4 

2.5 
4-5 



6-5 



§ 



0.6 
1.6 
0.6 
0.4 
2.3 
4.0 



5-5 



§ 



2SS 



0.5 
1.4 
0.4 
0.3 

2.1 

3.4 



0.3 



©2© 

8 S3 



0.4 0.3 

1.2 1.1 
0.3 0.2 



0.2 



1.9 1.7 
3-2 3-2 



4.8 4-2 3-6 



>o 
OS 



0.2 
1.0 
O.I 
0.2 

1-5 
3-0 



3-o 



* Supervision is to be omitted when superintendence is charged for. 

t The percentages noted in the case of alterations are to be computed 
on the value of the work involved in the alteration, not on the cost of the 
whole work. 



THE A.- LIETZ COMPANY. I93 

When employed on a per diem basis the charges for services 
should not be less than ten (10) dollars per clay for self or represen- 
tative and expenses. 

"When in charge of work as superintendent of construction the 
per diem should not be less than fifteen (15) dollars and expenses. 

The several items of payment on the percentage basis become due 
when the class of service covered by each has been rendered. 

All percentages are to be computed on the contract price or actual 
cost of the work. Pay for supervision or superintendence becomes due 
on the progress estimates made for contracts, or, if the work is done 
by day's labor, then on monthly appraisements of the value of the work 
done. 

In submitting plans and specifications the preliminary work, 
which generally involves the presentation of a satisfactory design is 
always presumed to have been done, and pay for preliminaries (except 
when such work has been undertaken at a salary or on a per diem 
basis), becomes due on presentation of plans and specifications, even 
when no actual field work nor the preparation of a preliminary design 
was necessary. 

When work covered by plans and specifications is not carried out, 
then compensation for preliminaries, plans and specifications is to be 
computed on the estimated cost of the work. 

The schedule rates are intended to cover compensation only for 
engineering services, i. e., compensation to the engineer for his services 
and for the services of his engineer assistants. The foregoing sched- 
ule rates do not include expenses, such as transportation, the hire of 
helpers, rod men, chain men, teamsters, living expenses when away 
from regular place of business, etc. All such expenses incurred by 
the engineer are a separate and additional charge against the owner. 

The schedule rates do not include pay for legal or expert services 
required of the engineer in charge of work when his services 
as arbitrator or as expert witness in settlement of controversies, con- 
demnation proceedings, etc., are required in the interest of the owner. 
For all such service and for every service not strictly included in the 
items specially enumerated in the schedule, the engineer is entitled to 
additional pay. Surveys which are not necessarily a part of super- 
intendence, such as location surveys for canals, roads, etc., which pre- 
cede the staking out of the work for the contractor, are not covered 
by any of the items in the rate schedule. 



194 



MODERN SURVEYING INSTRUMENTS. 



Sec. 12. Minimum rates for property subdivision and original 
townsite surveys, when the tracts to be subdivided do not lie within 
the corporate limits of cities or towns. 

(This being a table of minimum rates; smooth surfaced, practi- 
cally level, open ground and rectangular work has been made the basis 
thereof, and charges for subdivision work under less favorable con- 
ditions should be greater in proportion to the additional labor involved 
in field work, office computation and drafting.) 

MINIMUM RATES FOR SUBDIVISION SURVEYS. 



Area of 
Lot 


• 

Area in Acres of Tract to be Subdivided 


Acres 


5 to 10 


10 to 20 


20 to 50 


50 to 100 


100 to 200 


200 to 500 


Over 500 


20.0 

10. 

5-0 

1.0 

o.5 

0.1 


$ 

15-00 

7-50 
5.00 
1.50 


$ 

20.00 

10.00 

5.00 

3.50 

1.25 


$30.00 
15.00 
7.50 
4.00 
3.00 
1. 00 


$20.00 
12.50 

6.00 

3.50 
2.50 
0.80 


$15.00 
10.00 

5.00 
3.00 

2.00 
0.60 


$12.50 
8.50 
4.50 
2.50 
1.50 
0.45 


$10.00 

7.50 

4.00 

2.00 

1.25 
0.04 



Rates for lots of sizes intermediate between those named in the 
foregoing schedule are to be ascertained by interpolation. 

These rates do not include surveys of exterior boundaries of the 
tract to be subdivided, nor the cost of stakes or monuments to be set 
at corners or on base lines, which are to be furnished, marked or 
painted at owner's expense. 

The cost of planning subdivisions is included in the schedule rates, 
only when the same can be made without reference to topograhpical 
features or local conditions requiring a preliminary survey. 

The tabulated rates per lot include the preparation of one map 
and one tracing thereof. 

In case of alterations, each such alteration is to be charged for 
as extra work, provided the alteration is ordered after the subdivision 
survey has been commenced. When subdivisions of a complicated 
nature are required, which involve special study of the ground, the 
establishment of grade or irregular lots, it will generally be advisable 
to charge for the same on an agreed per diem basis. 

Sec. 13. The civil engineer should always charge for professional 
advice, regulating his charges according to the interests involved, 
whether his client be a private citizen, a corporation, or a municipality. 



THIi A. LIETZ COMPANY. I95 

Sec. 14. For services as an expert, whether before a court or 
as an arbitrator, special charges are to be made as may be mutually 
agreed upon by the employer and the engineer in accordance with the 
value of the service rendered, but in no case should the same, if fixed 
on a per diem basis, be less than twenty-five dollars per day. 

Sec. 15. Consultation with engineers who have made certain 
branches of professional work a specialty, or who have acquired a pre- 
eminent standing in the profession, may be requested by the engineer 
having general charge of any work or may be required by the owner 
thereof. In either case the employment of the consulting engineer 
must be satisfactory to both owner and engineer and shall be at the 
expense of the owner. 

No engineer should agree to act as consulting engineer except at 
the request or with the consent of the engineer in direct charge of the 
work ; and his reports and advice should be confined to the particular 
matters with reference to which he has been consulted. 

Charges for consultation should be based on the value of the ser- 
vices rendered rather than on time required in arriving at conclusions 
-or opinions. 

Sec. 16. No reputable engineer should participate in competitive 
bidding against his colleagues to secure work at lowest prices ; and 
calls for such competitive bidding should be discouraged. 

Sec. 17. Participation by engineers in competitions for the 
adoption of plans according to merit, or where prizes are offered is 
always undesirable, and should be considered permissible only when 
the decision as to merit rests with persons technically educated and 
competent to pass judgment thereon. 

Sec. 18. The owner's interests cannot be conserved when con- 
tracts for the construction of any work are let to the same person or 
firm which has furnished the plans and specifications therefor, and no 
reputable engineer should be interested in any contract for work to 
be executed according to plans and specifications furnished by himself. 

Sec. 19. The foregoing sections are not intended to apply in 
case of the employment of assistants or deputies by members of the 
profession, nor is Section 13 intended to make advice given by any 
engineer to a colleague at the latter's request, basis for remuneration 
from the owner, except when the owner consents to have such advice 
called for; but it would certainly be unprofessional to call for advice 
from a colleague except after proper provision has been made to pay 
for the same. 



INDEX 



PAGE 

Abney Hand Levels 164 

Address an instrument to the Company, how to 63 

Adjusting Department, the ; 8 

Adjustments, charges for 62 

collimators for 23 

of the dumpy level 73 

of the plane-table alidade 77 

of the transit 64 

of the Y-level 69 

Agate fittings for Y-level 51, 150 

Agate setting for needle 33 

Air meters (see Anemometers) 

Airy eye-piece, the 41 

Alidade, adjustment of the 77 

the plane-table 54 

of aluminum 56 

Altimeter, Abney's 164 

Aluminum alloys 54 

adaptability of 54, 57, 101 

alidade 56 

instruments, stability of 54, 139 

levels 56 

solar attachments 55 

transits 55 

Anemometers 169 

Aneroid barometers 165-7 

Architect's level 153, 154 

leveling rods 171, 172 

Attwood Mining Clinometer 163 

Axes of transit telescopes 35 

Balsam used in lenses 46 

Band chains . 181, 183 

Barograph (self-registering aneroid) 167-8 

Barometers, Aneroid 165-7 

Bell metal, use of 49, 55 

Bending of plates and centers 59 

Bessel's spheroid, elements of 104 

Binoculars 187, 189 

Biram's Anemometers 169 

Books, cross section 186 

field 185, 186 

level 186 

transit 185, 186 



I98 INDEX. 

TAGE 

Builders' level 153, 154 

transit 155, 156, 157 

Compass, clinometer 162, 163 

pocket 161 

surveying 160 

Careless handling of instruments 57 

Care of instruments 57 

Case, the instrument 46, 51, 101 

Centering the field of view 66 

Center pin for needle, adjusting 33, 60 

Centers, bending of 59 

length of : 30 

of dumpy level 52 

of Y-level 48 

of vertical axis, the 30 

single, cyclotomic 117, 122 

Chain pins 175 

Chains, surveyors' 176 

Chromatic aberration, test for 75 

Circle, horizontal 31 

" vertical 35 

adjustment of 68 

Clamp screws 32, 101 

Clarke's spheroid, elements of 104 

Clinometers 162-3 

Cloth-finish, dumpy level 52 

Y-level 50 

telescope standards 35 

Clothing, influence on needle 60 

Collars of the Y-level 49 

the inequality of 71 

Collar test, the 71 

Collimation, line of , 65-6 

Collimators, the mural 23 

Compass, graduation of the 34 

needle 33, 101 

repairs to 62 

surveyors' 160 

Conical bearings of telescope axis 35 

Construction of instruments 101 

Cord for plumb-bobs 175 

Correspondence regarding repairs 61 

Cost of repairs 62 

Cross-hairs, adjustment of 65, 71, 73 

frame for 43 

glass diaphragm for 44 

how to replace 60 

Crown glass in lenses 41 

Current meter 170 



THE A. LIETZ COMPANY. I99 

PAGE 

Cyclotomic transit 117, 22 

Definition of telescopes 50, 74 

Dumpy level, the 51 

adjustment of 70 

centers of 52 

cloth-finished 52 

price of 151, 152 

Eccentricity 30 

graphical determination of ■ 102 

Emery, danger of using 59 

Engineers' field books , 185, 186 

Eye-piece, the 41 

care of , 60 

the Airy 41 

the erect 41 

the Huyghens , 41 

the inverting 41 

the Kellner 41 

the negative 41 

the positive 41 

the Ramsden 41 

the Steinheil 42 

the terrestrial 41 

Field books 185, 186 

glasses 187, 189 

Finish of instruments, the 46, 50, 102 

Flag poles (see ranging poles) 

Flatness of field, test for 75 

Flint glass in lenses 41 

Flexible leveling rods 172 

Focal length, apparatus for determining the 76 

Focal length of objectives 41 

Fretting of working parts 58 

Gauge, rain 169 

Glass diaphragms for cross-lines 44 

Gradienter, observing horizontal distances by the 36 

Gradienter, the 26 

Graduation, accuracy of lines 99 

of compass 34 

on solid silver 31 

plate, the 20 

room, the Illustration, front part 

Hand levels 164 

How to tell a good surveying instrument 99 

Huyghens eye-piece, the 41 

Illumination of cross-hairs 43 

Jena Glass Works 27 

Johnson Plane-table 1°8 

Kellner eye-piece, the 41 



200 ' INDEX. 

PAGE 

Lamps, illuminating 159 

Lamps, plummet 159 

Latitude coefficients, table of 114 

length of one minute of 106 

Lenses, balsaming of , 46 

centering of 42, 45, 60, 70 

cleaning of 60 

- " staining of 60 

transit telescope 37 

Level, dumpy (see D) 51 

builder 153, 154 

hand 164 

instrument 48 

McCullough tape 184 

reflecting (Abney's) 164 

reversion 130 

" rod 173 

" screws 29 

sensitiveness of bubble , 36, 48, 62 

Y-Level, the 48 

adjustments 69 

" agate fittings 51 

" aluminum A 55 

" center of 48 

cloth-finish of , 50 

collars of 49 

" curvature of tube 48 

magnifying power of 49 

" packing in case 51 

precision 51 

price of 149, 150 

" repairs to 62 

Leveling poles 171, 172, 173 

Leveling rods 171, 172 

Lifting arrangement of needle 33 

Line for plumb-bobs 175 

Locke's hand levels 164 

Longitude, how to find the length of one minute of 104 

Lubrication of certain parts 58 

Magnetic attraction in clothing 60 

Magnetic needle 33, 101 

Magnetic variation, to set off the 128 

Magnifying power of telescopes 45, 48 

" to find the 76 

Marking tools 175 

Marine glasses 187, 189 

Measuring chains 176 

tapes 176, 183 

Meter, current 170 



THE A. LIETZ COMPANY. 201 

PAGE 

Alining aneroids 167 

field books 185, 186 

Mining transit, with inclined standards Front part of manual 

Nautical mile, length of 106 

Needle, the magnetic 33, 101 

" center-cap of 33 

center-pin of 33 

lifting arrangement of 33 

to restore magnetism of 60 

to preserve sensitiveness of 58 

Nonius, the 31 

Obj ect glass, the 41 

Objectives, focal length of. 42 

Odometers 175 

Optical axis, coincidence of 42, 46, 60, 70 

Orthoscopic eye-piece 42 

Packing transit in case 46 

level in case 51 

Paine's pattern tapes 176, 178 

Parallax, adjustment of 64, 71 

Parallelism of collars in Y-level 69 

telescope in Y-level 71 

Passometer 175 

Pedometers 175 

Plane-table, the 53, 54 

Plane-table 158 

adjustment of alidade 77 

price of 158 

Plates, bending of 59 

horizontal 30 

" levels for *: 64 

Plumb-bobs 174 

Plumbing arrangement 29 

Plummet lamps 159 

Pocket compasses 161, 162, 163 

Pocket thermometer 177 

Poles, ranging 171, 173 

Poles, sight 171, 172, 173 

Prices of dumpy level 151, 152 

preliminary transit . 155, 157 

Y-level 149, 150 

plane-table 158 

theodolite 135, 136, 143, 144 

transit, complete 130, 148 

compound mining and solar 145, 148 

cyclotomic on application 

mining 139 

mountain and mining 137, 138 

plain 127, 129 



202 INDEX. 

PAGE 

Prices of transit, with telescope level 128, 129 

compasses , 160, 163 

Prism binoculars 187, 188 

Prismatic compasses 162 

Protection from rain 58 

" sun 58 

Rain gauges 169 

Ramsden eye-piece, the 41 

Ranging poles 171, 173 

Refraction correction table 115, 116 

Refraction table, mean Ill 

Registers, water 170 

Remarks on instruments 53, 99 

Repairs 61 

" cost of 62 

what to send 62 

Reversion level 130 

Right-angles, arrangement for laying off , 46 

Rods, leveling 171, 172 

" sight 171, 172 

stadia (flexible) 172 

Rod, level 173 

Saegmuller Solar Attachment 46, 55, 107 

Screws, overstraining 58 

Shake in the slide 42 

tripod 59 

Shifting center „ 31, 101 

Shipping an instrument 63 

Shoes, tripod • 47 

Sights—Masses 160, 163 

Sighting poles (see ranging poles) 

Silver, graduation on solid 31 

Size of transits 46 

" levels 149, 154 

Slide, the 42, 58 

protector, the 42, 50 

scale, the logarithmic 92 

Solar attachment 46 

of aluminum 55 

Saegmuller 46, 55, 107 

Spherical aberration, test for 74 

Spheroid, elements of the terrestrial 104 

Spider web, the 43 

Spirit levels (vials) 36 

importance of sensitive 36 

Split leg tripods 158 

Stability of instruments 29, 101, 140 

" aluminum instruments 54, 101 



THE A. LIETZ COMPANY. 203 

PAGE 

Stadia hairs, fixed . .44, 51, 52 

" adjustable 44 

Stadia reduction tables 88 

" surveying, treatise on , 81 

Stake tacks 175 

Standards, the 35, 101 

unequal expansion in 35 

Star-shaped casting for leveling screws 29, 101 

Steel center in Y-level . . . . 48, 55 

Steel tapes ( see tapes ) 

Steinheil eye-piece, the 42 

Sunshade, the 43, 51 

Surveying aneroids 167 

chains 176 

Surveying instrument, how to tell a good 99 

Surveyors' pins 175 

Tables, mean refraction Ill 

of latitude coefficients 114 

refraction correction . . . 115, 116 

" stadia reduction 88 

Tacks, stake 175 

Tangent screws 32, 101 

Tape lines (steel and metallic) 176, 183 

ribbons . 183 

Tapes, measuring 176, 183 

Telescope, accurate balance of 45 

bearings, adjustment of 65 

cleaning of 61 

definition of 74 

finding the magnifying power of a 76 

general remarks on 45, 99 

level 49 

adjustment of 67, 71 

magnifying power of 45 

reversibility of transit 45 

test of 74 

transit 27 

" adjustment of 65 

Testimonials (on first leaves of Manual). 

Theodolite, description of 26 

highest grade 54 

price of , 135-6. 143-4 

size of 136, 144 

Three-leveling-screw arrangement 29 

Thermographs 177 

Thermometers, pocket 177 

Transit, adjustments of the 64, 69 

" aluminum 54 

" centers of 29 



204 INDEX. 

PAGE 

Transit, cyclotomic 117, 122 

description of 26 

packing in case , 46 

price of 127, 148 

repairs to 62 

single center, cyclotomic 117, 122 

sizes of 127-148 

Transit books 185, 186 

Tripod connection , . . , 16, 101 

coupling, the new Lietz 16 

" shake in 59 

split leg 47 

Tripods , 158 

Variation, setting off the magnetic 34 

plate . . 34 

Vernier, the 31 

position of 32, 101 

protected by glass 32 

" shades 32 

theory of the 32 

Vertical arc 35 

' adjustment of the 68 

Water Registers 170 

Watch pattern anemometers 169 

Werner, Peter 32 

Wind gauges 169 

Y-level ( see level ) 48 

Zero of vertical arc 68 



Printed by *Ef)e g>tanlep.8Faptor Company, San Francisco 



}Ai^ 10 1908 



LIBRARY OF CONGRESS 



001 941 141 2 ft 



